Monitoring or feedback systems and methods

ABSTRACT

The present invention generally relates to systems and methods for monitoring and/or providing feedback for drugs or other pharmaceuticals taken by a subject. In one aspect, the present invention is directed to devices and methods for determining a species within the skin of a subject; and producing feedback to a subject based on the determination of the species. The feedback may be, for example, visual, audible, tactile, a change in temperature, etc. In some cases, information regarding the determination of the species may be transmitted to another entity, e.g., a health care provider, a computer, a relative, etc., which may then provide feedback to the subject in some fashion. In some cases, the feedback may be directly indicative of the species, e.g., whether the species is present, the concentration of the species, whether a by-product of a reaction involving the species is present, whether a compound affected by the species is present, etc. However, the feedback may also be indirect in some embodiments. For example, the subject may be presented with an external reward, e.g., based on the determination of the species within the skin. For instance, a reward such as cash, coupons, songs, discounts, personal items, etc., may be offered based on the level of compliance of the subject. Still other aspects of the invention are generally directed to kits involving such devices (with or without the drug to be monitored), methods of promoting such systems, or the like.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/299,283, filed Jan. 28, 2010, titled “Monitoringor Feedback Systems and Methods,” by Levinson, et al., incorporatedherein by reference.

FIELD OF INVENTION

The present invention generally relates to systems and methods formonitoring and/or providing feedback for drugs or other pharmaceuticalstaken by a subject.

BACKGROUND

One problem often faced by physicians and other health care providers isthat drugs and other pharmaceuticals that are prescribed to subjects arenot taken by the subjects, or are not taken properly by the subjects.The reasons for non-compliance or poor compliance vary, and includeforgetfulness, cost, inconvenience, lack of follow-up, or fear of takingmedications. Accordingly, techniques for monitoring or improvingcompliance are needed.

SUMMARY OF THE INVENTION

The present invention generally relates to systems and methods formonitoring and/or providing feedback for drugs or other pharmaceuticalstaken by a subject. The subject matter of the present inventioninvolves, in some cases, interrelated products, alternative solutions toa particular problem, and/or a plurality of different uses of one ormore systems and/or articles.

In one aspect, the present invention is generally directed to a device.In one set of embodiments, the device includes a sensor able todetermine a species withdrawn from a subject, and an indicator able toindicate an external reward based on the determination of the species.In another set of embodiments, the device includes means for determininga species withdrawn from a subject, and means for providing an externalreward based on the determination of the species.

In some embodiments, the device includes a sensor configured, adapted ordesigned to determine a species withdrawn from a subject, and a deviceindicator, responsive to the sensor and configured to indicate anexternal response based on the determination of the species.

In accordance with yet another set of embodiments, the device includes asensor able to determine an amount and/or concentration of a specieswithdrawn from a subject, and a component able to produce non-numberfeedback related to the amount or concentration of the species.

In some embodiments, the device includes means for sensing a specieswithdrawn from a subject, and means for indicating an external rewardbased on the sensing of the species. In certain instances, the deviceincludes means for withdrawing a species from a subject using a devicefastened to the subject, means for determining information comprising anamount and/or a concentration of the species using at least the device,and means for transmitting the information to a computing device,wherein the computing device is configured to provide, via an outputdevice, non-number feedback to the subject based on the transmittedinformation. In one set of embodiments, the device includes means fordetermining information representing a property of a species withdrawnfrom a subject using a device immobilized to the skin of the subject,and means for transmitting the information to a machine configured tocause an external response to be presented to a user of the machine.

The present invention, in another aspect, is directed to a method.According to one set of embodiments, the method includes acts ofdetermining a species withdrawn from a subject using a device fastenedto the subject, and providing an external reward based on aconcentration of the species. In another set of embodiments, the methodincludes acts of determining a species withdrawn from a subject, onmultiple days, using one or more devices able to be fastened to theskin, and providing an external reward based on the number ofdeterminations. The method, in yet another set of embodiments, includesacts of determining an amount and/or concentration of a specieswithdrawn from a subject using a device fastened to the subject, andproducing non-number feedback indicative of the determination of thespecies.

In one set of embodiments, the method includes acts of determininginformation relating to a species withdrawn from a subject, transmittingthe information to a computer, and causing the computer to providefeedback to the subject based on the information relating to thespecies. In another set of embodiments, the method includes acts ofreceiving information obtained from a subject representing a property ofa species withdrawn from the subject, and presenting an external rewardto a user based on the received data. The method, in still another setof embodiments, includes acts of determining information representing aproperty of a species withdrawn from a subject using a device fastenedto the subject, and transmitting the information to a machine capable ofcausing an external reward to be presented to a user of the machine.

In one set of embodiments, the method includes acts of withdrawing aspecies from a subject using a device fastened to the subject,determining information comprising an amount and/or a concentration ofthe species using at least the device, and transmitting the informationto a computing device. In some cases, the computing device is configuredto provide, via an output device, non-number feedback to the subjectbased on the transmitted information.

The method, in certain embodiments, includes acts of receivinginformation obtained from a subject representing a property of a specieswithdrawn from the subject, and presenting an external response to auser based on the received data.

In some embodiments, the method includes acts of determining informationrepresenting a property of a species withdrawn from a subject using adevice immobilized to the skin of the subject, and transmitting theinformation to a machine configured to cause an external response to bepresented to a user of the machine.

The method, according to one set of embodiments, includes acts ofadministering a drug to a subject, determining a species withdrawn froma subject that is indicative of the drug administered to the subject,and providing feedback to the subject regarding the species. In someembodiments, the drug administered to the subject is not distinguishablefrom a placebo by the subject without any external equipment. In someembodiments, the method includes acts of administering a drug to asubject, determining a species withdrawn from a subject that isindicative of the drug administered to the subject, and providingfeedback to the subject regarding the species. In some cases, the drugadministered to the subject can not be distinguished, by the subject,from a placebo without any external equipment.

In yet another set of embodiments, the method includes acts ofadministering a drug to a subject having a condition suspected of beingtreatable by the drug, determining a species withdrawn from a subjectthat is indicative of the drug administered to the subject, andproviding feedback to the subject regarding the species. In some cases,the drug does not cause a measurable change to the condition of thesubject within the first 24 hours after administering the drug. Inaccordance with certain embodiments, the method may include acts ofadministering a drug to a subject having a condition suspected of beingtreatable by the drug, determining a species withdrawn from a subjectthat is indicative of the drug administered to the subject, andproviding feedback to the subject and/or another person regarding thespecies. In some instances, the drug does not cause a measurable changeto the condition of the subject within the first 24 hours afteradministering the drug.

In another aspect, the present invention is directed to a method ofmaking one or more of the apparatus embodiments described herein. Inanother aspect, the present invention is directed to a method of usingone or more of the apparatus embodiments described herein.

Other advantages and novel features of the present invention will becomeapparent from the following detailed description of various non-limitingembodiments of the invention when considered in conjunction with theaccompanying figures. In cases where the present specification and adocument incorporated by reference include conflicting and/orinconsistent disclosure, the present specification shall control. If twoor more documents incorporated by reference include conflicting and/orinconsistent disclosure with respect to each other, then the documenthaving the later effective date shall control.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting embodiments of the present invention will be described byway of example with reference to the accompanying figures, which areschematic and are not intended to be drawn to scale. In the figures,each identical or nearly identical component illustrated is typically(though not necessarily) represented by a single numeral. For purposesof clarity, not every component is labeled in every figure, nor is everycomponent of each embodiment of the invention shown where illustrationis not necessary to allow those of ordinary skill in the art tounderstand the invention. In the figures:

FIG. 1A-1B illustrate devices according to certain embodiments of theinvention;

FIGS. 2A-2C illustrate devices according to various embodiments of theinvention;

FIG. 2D illustrates a kit containing more than one device, in yetanother embodiment of the invention;

FIG. 2E illustrates a device according to still another embodiment ofthe invention;

FIGS. 3A-3B illustrate certain methods in accordance with variousembodiments of the invention; and

FIG. 4 is a schematic diagram illustrating a device transmittinginformation about a species from a subject to a device able to offer areward, in accordance with one embodiment of the invention.

DETAILED DESCRIPTION

The present invention generally relates to devices and methods fordetermining a species within the skin of a subject; and producingfeedback to a subject based on the determination of the species. In someembodiments, the invention is generally related to systems and methodsfor monitoring and/or providing feedback for drugs or otherpharmaceutical substances taken by a subject. The feedback may be, forexample, visual, audible, tactile, a change in temperature, etc. In somecases, information regarding the determination of the species may betransmitted to another entity, e.g., a health care provider, a computer,a relative, etc., which may then provide feedback to the subject in somefashion. In some cases, the feedback may be directly indicative of thespecies, e.g., whether the species is present, the concentration and/oramount of the species, whether a by-product of a reaction involving thespecies is present (and, if so, perhaps in what amount and/orconcentration), whether a compound affected by the species is present(and, if so, perhaps in what amount and/or concentration), etc. However,the feedback may also be indirect in some embodiments. For example, thesubject may be presented with an external reward, e.g., based on thedetermination of the species within the skin. For instance, a rewardsuch as cash, coupons, songs, discounts, personal items, etc., may beoffered based on the level of compliance of the subject. Still otheraspects of the invention are generally directed to kits involving suchdevices (with or without a drug or other substance to be monitored),methods of promoting such systems, or the like.

In one aspect, the present invention is directed generally to devicesable to monitor or provide feedback to a subject taking (or not taking)a drug or other pharmaceutical substance, and/or to provide suchfeedback to other personnel. For example, feedback may be provided to arelative of the subject, a caregiver for the subject, medical personnelcaring for the subject (e.g., a nurse, a doctor, etc.), or the like.Thus, in one set of embodiments, feedback may be provided to anyone whowould communicate such feedback to the subject. The subject is typicallyhuman, although the subject may be non-human in some cases. The feedbackgiven to the subject may be based on information regarding thedetermination of the drug or other pharmaceutical substance, forexample, an amount and/or concentration of the drug or otherpharmaceutical substance within the subject. The determination may bequalitative (e.g., determining the presence or absence of the drug orother pharmaceutical substance) and/or quantitative (e.g., determiningan amount and/or concentration, etc.). For instance, the feedback mayinclude information regarding the subject's compliance with taking (ornot taking) one or more drugs or other pharmaceutical substances.Depending on the personnel, additional information may be given to thesubject, e.g., warnings about compliance (or lack thereof), informationabout potential drug interactions, suggestions for improving compliance,suggestions for changes in lifestyle, or the like.

A non-limiting example of such a process is now described with respectto the flowchart shown in FIG. 3A. In this figure, a device is appliedto a subject 321, e.g., by the subject (i.e., self-administered) oranother person (e.g., a health care provider). The device is thenactivated (or in some cases, self-activated) to withdraw fluid 322 fromthe subject, e.g., blood, interstitial fluid, etc. The device may thenanalyze the fluid for one or more species, e.g., using one or moresensors as discussed herein. In some cases, analysis of the speciesoccurs on the device itself. In certain instances, information about thespecies (e.g., the presence and/or absence, concentration, amount, etc.)is transmitted externally of the device, e.g., to a computing device,which may also in some embodiments return a signal to the device. Aftersuch analysis, if certain conditions are met, the device may activate anindicator 323 (e.g., light, sound, graphics, music, etc.) which alertsthe subject (or another person) that an external reward or punishment isavailable. The subject (or another person) can then access a computingdevice 324 (which may be the same or different from the computing devicediscussed above) to access the external reward and/or to determine whatpunishment is to be applied. The computing device may, for example,display a weblink to access the reward or punishment, and/or there maybe an output device able to output a reward (e.g., a coupon or acertificate).

A schematic illustration of such a system is shown in FIG. 4. In thisfigure, a device 44 for withdrawing a fluid is placed on a portion of asubject 41 (e.g., an arm or a leg), and in some cases, immobilizedthereto (for example, using an adhesive). After withdrawing a samplefrom the subject (e.g., blood or interstitial fluid), device 44determines one or more species suspected of being present within thesample using one or more sensors. Information from the sensors may beanalyzed by device 44, and/or transmitted 48 to an external computingdevice 47. For example, device 44 may determine the presence of aspecies, and in some cases, determine if an external reward (orpunishment) should be offered to the subject. If an external computingdevice is used, any method of transmission to the computing device maybe used, including wireless or radio transmissions. In some cases,external computing device 47 may also send a signal back to device 44.For example, in some embodiments, external computing device 47 may beused to analyze the species and determine if an external reward (orpunishment) should be offered to the subject. Thus, information aboutthe species and/or whether such an external reward or punishment shouldbe offered may be transmitted back to device 44.

If it is determined that the subject should be offered an externalreward (or punishment), device 44 may activate a suitable indicator 43to inform the subject (or another person). For example, indicator 43 maybe include a display screen, a speaker, a light or an LED, or the like,e.g., as discussed herein. Computing device 47, and/or another outputdevice 51, may then be used to offer the external reward (or punishment)to the subject (or other person). For example, the subject or otherperson may access computing device 47 and/or output device 51 to claimthe reward or accept the punishment.

The species to be determined within the subject may be present anywherewithin the subject, e.g., within or beneath the skin of the subject,and/or within other bodily fluids such as blood or interstitial fluid.The species may be an administered composition (e.g., a drug or otherpharmaceutical substance), and/or another species that is related tosuch a composition, such as a tracer or other compound taken with theadministered compound, for example, such as the systems and methodsdisclosed in U.S. Pat. Apl. Ser. No. 61/163,733, filed Mar. 26, 2009,titled “Determination of Tracers within Subjects,” by Douglas A.Levinson, or U.S. patent application Ser. No. 12/748,316, filed Mar. 26,2010, titled “Determination of Tracers within Subjects,” by Douglas A.Levinson, published as U.S. Patent Application Publication No.2010/0272652 on Oct. 28, 2010, each incorporated by reference herein intheir entireties. For example, the species to be determined may be theproduct of an interaction of the drug (or other pharmaceuticalsubstance) with the subject. As specific non-limiting examples, thespecies may be a metabolite of the administered composition; a productor by-product of the administered composition with the subject (forexample, a cleavage product); a marker for a condition that would beaffected by, or a disease that is treatable by, the administeredcomposition (for instance, a protein, a hormone, a small molecule,etc.); a species within the body that the administered (orto-be-avoided) composition interacts with (e.g., degrades), such as atarget of that composition (for example, a protein or enzymatic targetwithin the subject), or the like. Accordingly, in the descriptionherein, it should be understood that references to determining the drug(or other pharmaceutical or other administered substance) in the subject(e.g., in the skin, blood, interstitial fluid, etc. of the subject) areby way of example only, and in other embodiments, other species relatedto the administered composition may be determined in any suitablelocation within the subject, instead of or in addition to theadministered composition, such as those described herein.

As mentioned, in some embodiments of the invention, a species may bedetermined indirectly, for example, using a tracer of the species. Asused herein, a “tracer” is a substance that can be determined within asubject, typically upon interaction with an indicator. In some cases,the tracer is determinable in some fashion, e.g., by a sensor asdisclosed herein. For example, the tracer may be radioactive orfluorescent in some cases; although in other cases, the tracer may notbe radioactive and/or fluorescent. The determinable change in the tracerand/or the indicator may be a visual change such as a change inappearance (e.g., color), a change in temperature, a change insensation, or the like. The tracer itself may be any suitable compoundthat can be administered to the subject. In some cases, the determinablechange may be one that can be determined by a human without the use ofany equipment, for example, visually, tactilely, or the like. In othercases, the determinable change may be determinable using suitableinstrumentation.

In some cases, the tracer is chosen to have relatively little, oressentially no, biological activity, and can be determined mainly by itsinteraction with the indicator. However, in other cases, the tracer mayhave some biological activity. For instance, the amount of biologicalactivity of the tracer within the subject may be predictable. As anexample, a tracer may be cleared by the kidneys from the bloodstream ata certain rate, and by determining the concentration of tracer withinthe subject, e.g., by determining a change in a determinable property(e.g., a chemical property, a physical property, an electrical property,etc.) in an indicator, and correcting for the clearance rate of thetracer, the pharmacokinetic activity of the tracer within the subjectmay be determined, and used to determine the pharmacokinetic activity ofa substance administered to the subject. Usually, the tracer is producedexternally or exogenously, then administered to the subject as discussedbelow. Non-limiting examples of tracers include certain proteins orcarbohydrates such as inulin, or small molecules (typically less thanabout 1000 Da) such as creatinine.

The tracer may be relatively non-toxic in some cases. In one set ofembodiments, the tracer is a molecule that has a relatively high rate ofclearance from the body. For instance, the half-life of the tracerwithin the body may be less than about 3 days, less than about 2 days,less than about 1 day, less than about 18 hours, less than about 12hours, less than about 9 hours, less than about 3 hours, or less thanabout 1 hour. In some cases, the tracer may include poly(ethylene)glycol, for example, PEG 300, PEG 400, PEG 2000, PEG 3350, or PEG 8000(where “PEG” stands for poly(ethylene) glycol and the number indicatesthe molecular weight).

As a non-limiting example, the tracer may exhibit substantially the samepharmacokinetic activity as the administered substance, or at leastexhibit certain pharmacokinetic activities indicative of the substance.For instance, the tracer may exhibit similar absorption and/ordistribution rates within the body, the same duration within the body,the same metabolism within the body, or the same excretion rates fromthe body, e.g., through the urine. In other cases, however, the tracerand the substance may exhibit substantially different pharmacokineticparameters. For example, the tracer may exhibit substantially slower orfaster absorption or distribution within the body. However, bydetermining the tracer, e.g., using an indicator, an estimate of thepharmacokinetic activity of the substance within the body may still beobtained. In one embodiment, it may be sufficient to simply determinewhether the tracer is present or absent in the body, and then infer thatthe substance is also present or absent in the body based on the tracer(for example, if the subject is given a composition that comprises boththe tracer and the substance to be administered as a single entity). Insome cases, the amount of tracer delivered to the subject may also becontrolled in some fashion, for example, such that the certainpharmacokinetic activities of the tracer are substantially similar tothe pharmacokinetic activities of the substance also administered to thesubject. As non-limiting examples, the substance may be an alcoholicbeverage or a drug that is administered with a tracer, and the indicatorused to determine whether the subject has indeed taken the substance ornot.

Feedback may be provided in any suitable form. As mentioned, feedbackmay be provided to the subject or to other personnel. In some cases, thefeedback may be directly provided by the device, e.g., to the subjectafter determination of the species. In one set of embodiments, thefeedback may be auditory, visual, olfactory, tactile, thermal, or thelike.

For example, if the feedback is auditory, the feedback may includesounds such as jingles, songs, music, sound effects, or the like. Insome cases, the sounds may be selectable by the subject or otherpersonnel. For instance, the subject may select a first song indicatingcompliance, and a second song (or no song) indicating non-compliance;the subject may also select additional songs in some embodiments forother indications (e.g., partial compliance, a reminder to take thecomposition, a song indicating successful compliance over somepredetermined period of time or number of administrations, etc.). Soundmay be produced by a device using any suitable technique, for example,using a speaker or a relay clicker. Techniques for causing a speaker toplay music or sounds will be familiar to those of ordinary skill in theart. For example, the speaker may be a digital speaker that plays songsstored in a memory device, e.g., in any suitable format (e.g., flashmemory, magnetic tape, hard drive memory, optical media such as CDs orDVDs, or the like). Other types of sounds may be used in otherembodiments, for example, sound effects (e.g., beeps, buzzes, jingles,etc.), synthesized sounds or speech, verbal reminders, or the like.

As another example, the feedback may be tactile. One non-limitingexample of a tactile sensation is a change in temperature (e.g., gettingwarmer or cooler), for example, using electronic heating or coolingdevices such as resistive heaters or Peltier coolers. Thus, as aparticular example, a device may be worn that produces heat or coolingwhen compliance is lacking, thereby reminding the wearer to administerthe drug or other pharmaceutical substance. As other examples of tactilefeedback, the device may vibrate, tighten or loosen, etc. to indicatecertain conditions, e.g., as positive or negative feedback provided tothe subject. For instance, the device may be worn around the arm (e.g.,as in a bracelet or wristwatch), and the device may tighten around thearm if the subject has or has not been compliant.

In yet another set of embodiments, the feedback may be visual. Forexample, the device may include an output device including one or morelights, LEDs, LCDs, a screen able to display an image, or the like. As aspecific non-limiting example, lights may be provided that are red whencompliance is lacking and green if the subject exhibits adequatecompliance. In some cases, the lights may also flash, e.g., to getattention. Other lights may be provided in other embodiments, forexample, to indicate that the next administration is due, to indicateoperation of the device, to indicate successful compliance over somepredetermined period of time or number of administrations, etc. Asanother example, a light within the device may be used to produce a logoor an advertisement when the composition has been taken, etc. In somecases, the feedback may be non-number based, i.e., the feedback does notinclude the display of numbers, but instead contains other methods orsymbols to indicate feedback, e.g., lights, bars, plots, signals,graphs, logos, or the like. As still another example, the device maydisplay numbers, a series of lights, pictograms, LEDs, LCDs, logos,etc., indicating information regarding the species within the subject,for example, the concentration, the number of times the drug or otherpharmaceutical substance was taken by the subject, the time since thelast administration of the drug or other pharmaceutical substance waspreviously administered, the time before the next administration, or thelike. If a screen is used, the screen may be able to display arbitraryinformation, e.g., regarding operation of the device, informationregarding the species within the subject, information regardingadministration of the drug or other pharmaceutical substance, weblinksor hyperlinks, or other useful information, etc. In still anotherembodiments, the device may produce a desirable display of lights,logos, advertisements, movies, etc., as a reward for successfulcompliance.

These may also be combined in still other embodiments. For example, thedevice may produce a movie with sounds to indicate compliance (or lackthereof), the device may produce blinking lights during or following asong, or the like.

In one set of embodiments, the feedback that is provided by the devicemay be related to the drug or other pharmaceutical substance in someway. For example, the feedback may indicate whether the drug (or otherpharmaceutical substance) was taken or not, the degree of compliance,the concentration of a species within the subject (measured directly orindirectly, e.g., by determining a metabolite within the subject), thetime since the drug or other substance was taken, the time until thenext administration of the drug, the number of administrations, etc. Insome of embodiments, the feedback may be a reward indicating some degreeof successful compliance. For example, feedback may be provided afterthe subject has taken the drug or other substance, after the subject hastaken the drug or other substance a certain number of times, after thesubject has taken the drug or other substance for a certain period oftime, once a certain concentration (e.g., high or low) of a specieswithin subject has been reached, or the like. The feedback may benumerical and/or non-numerical. Such feedback may, in some embodiments,be of sufficient value to the subject that the subject may behave in acertain way, e.g., increasing compliance or continuing taking the drugor other pharmaceutical substance. In other embodiments, as discussedherein, the feedback may include a reward, such as an external reward orother external response (e.g., a punishment). The reward may alsoinfluence the subject's behavior in some cases.

In some cases, feedback may be provided to the subject in real time,e.g., by the use of a graph, numbers, lights, etc. As a particularexample, the device may display a number that indicates theconcentration or amount of a species within the subject (e.g., glucose),and optionally, when a certain concentration is reached, the device mayalso indicate to the subject in some fashion that a medication (e.g.,insulin) is needed, for example, by activating a light, displaying alogo, playing a sound or a song, or the like.

As illustrated in the example of FIG. 3B, the device, in one set ofembodiments, may be operated as follows. A sample may be withdrawn froma subject to which the device is applied 331. For example, the samplemay be blood, interstitial fluid, or the like. The device then analyzesthe sample 332 to determine one or more species within the sample, e.g.,the presence and/or absence, amount, concentration, etc. For example,one or more sensors as discussed herein may be present within thedevice. In some cases, analysis of the species occurs on the deviceitself. In certain instances, the device interfaces with an externalcomputing device 333 so that information about the species (e.g., thepresence and/or absence, concentration, amount, etc.) can be transmittedexternally of the device, e.g., to a computing device, which may also insome embodiments return a signal to the device. Based on such analysis,the device may then activate an indicator 334, for example, light,sound, graphics, music, etc. to alert the subject (or another person)that an external reward (or punishment) is available. In some cases, thedevice itself may perform the analysis of the species and activate theindicator, prior to interfacing with an external computing device.

The device may be used once, or multiple times. For instance, in one setof embodiments, the device may be used to determine a species within theskin at multiple points of time, e.g., on multiple days, or evencontinuously in some instances. Feedback may be provided to the subjectimmediately or within a short time after determining the species, and/orinformation regarding the species may be stored for later use (e.g., asdiscussed below). For instance, in one set of embodiments, after thesubject has taken the drug or other substance a certain number of times,or after a certain number of days, feedback may be provided to thesubject, for example, in the form of a reward or punishment as discussedbelow.

As discussed, in one set of embodiments, feedback is provided by thedevice itself. However, in another set of embodiments, feedback may beprovided by another entity. The entity may be another person (such as arelative, medical personnel, etc.), or a non-living entity, such as acomputing device or an Internet-based service. For example, informationabout the species may be transmitted to the other entity, which may thenprovide feedback to the subject in a suitable fashion. Examples ofcomputing devices include, but are not limited to, general purposecomputers, specially-built computers, application-specific integratedcircuits, microprocessors, or the like. In some cases, the computingdevice may interface with an output device, e.g., configured to providefeedback such as is discussed herein, for instance, visual feedback,auditory feedback such as music, etc. In some embodiments, after adevice determines a species, an indicator on the device may be used toindicate that an external reward (or punishment) is available based onthe determination of the species, for example, on a web site or anoutput device. Examples of indicators include screens, lights, speakers,etc., as is discussed herein.

One non-limiting example method of using the computing device is nowillustrated with respect to FIG. 3C. In this figure, an externalcomputing device (e.g., a general purpose computer, a specially-builtcomputer, an application-specific integrated circuit, a microprocessor,etc.) receives a transmission 351 from a device that is used to withdrawa sample from a subject for analysis. The sample may be, for example,blood or interstitial fluid. For example, the device may include one ormore sensors able to determine a species suspected of being presentwithin the sample withdrawn from the subject, and the device maytransmit sensor data, and/or the device may analyze sensor data andtransmit information about the species (e.g., the presence or absence,amount, concentration, etc.) to the computing device. In this example,based on the transmission, the computing device may determine if areward (or punishment) is appropriate 352, e.g., using criteria such asthose described herein. Optionally, the computing device (or anothercomputing device) may be used by the subject, or another person, toaccess an external reward or punishment 353. For example, the computingdevice may be a computer that a person can log into to receive theexternal reward. In some cases, the computer device may be connected toan output device for producing the external reward, e.g., a screen, aTV, a printer, a speaker, or the like.

In one set of embodiments, the device may transmit information regardingthe subject and/or administration of the drug or other pharmaceuticalsubstance to another entity. The information may be transmitted, e.g.,wirelessly (for example, using radio antennas, transceivers, infraredlight, laser light, visible light, acoustic energy, or the like), orthrough the use of wires (for example, using electronic ports such asparallel ports, serial ports, USB connections, RS232/485 communicationtransceivers, 4-20 mA analog transceivers, an Ethernet transceiver, orthe like). Any suitable transmission protocol may be used, e.g.,Bluetooth, Wi-Fi or IEEE 802.11, WiMax, peer-to-peer networking,Wireless FireWire, or the like. The information may be transmittedrelatively quickly after determination of a species within the subject,and/or the information may be stored for later transmission and/orretrieval, for example, by the subject, or by another person.

If information is stored on the device, any suitable technique may beused to store such information, e.g., in a data storage compartment, forexample, silicon integrated circuits, magnetic media, optical media, orother kinds of data storage devices. In one embodiment, the data storagecomponent includes a computer-readable medium, for example, a mediumthat stores information through electronic properties, magneticproperties, optical properties, etc. of the medium. Examples ofcomputer-readable media include, but are not limited to, silicon andother semiconductor microchips or integrated circuits, radio frequencytags or circuits, compact discs (e.g., in CD-R or CD-RW formats),digital versatile discs (e.g., in DVD+R, DVD-R, DVD+RW, or DVD-RWformats), insertable memory devices (e.g., memory cards, memory chips,memory sticks, memory plugs, etc.), “flash” memory, magnetic media(e.g., magnetic strips, magnetic tape, DATs, tape cartridges, etc.),floppy disks (e.g., 5.25 inch or 90 mm (3.5 inch) disks), optical disks,and the like. In one set of embodiments, the data storage component maybe reversibly attached to and removed from the device. In someembodiments, the data storage component may be volatile, i.e., somepower is required by the data storage component to maintain the datatherein. In other embodiments, however, the data storage component isnon-volatile. In some embodiments, the data storage component is anelement that is constructed and arranged to allow data to be stored toand/or retrieved. In one embodiment, the memory or data storagecomponent includes a data storage chip. As used herein, a “data storagechip” is a microchip or microprocessor to which data can be storedand/or retrieved. Typically, the data storage chip comprises asemiconductor and often contains electronic circuitry.

In some embodiments, information regarding the subject and/oradministration of the drug or other pharmaceutical substance may beprovided to the subject or another person. For instance, the device maydetermine a species within the skin of a subject, then transmit theinformation regarding the species to another entity, e.g., a receiver, acomputer, a computing device, a web page on the Internet, etc., forretrieval and/or analysis by another person, e.g., the subject, arelative, medical personnel, etc. If another person is involved, theperson may provide feedback to the subject. For example, the personcould review information regarding the species, and/or make adetermination regarding compliance of the subject with administration ofthe drug or other pharmaceutical substance. In some cases, the personmay give advice (such as medical advice), warnings, encouragement,counseling, etc., to the subject regarding administration and/orcompliance issues. In addition, as previously discussed, in someembodiments, additional information may also be given to the subject,for example, information about potential drug interactions, suggestionsfor changes in lifestyle, methods for improving compliance, changes inprescription, or the like.

In one set of embodiments, the device may indicate that the subject (oranother person, as described herein) may have access to a web page. Thedevice may indicate access to the web page by any suitable technique,for example, visual, audible, tactile, a change in temperature, etc. Asnon-limiting examples, the device may turn on a light, display an imageor a logo, to produce a sound, play a song, etc. to indicate that theweb page is accessible, to indicate a change or an update in the contentof the web page, produce a reminder to review the web page, etc.

The web page may be used to display information to the subject, and/orto another person. For instance, in one set of embodiments, the devicemay transmit information to another entity (e.g., a computer or acomputing device), and the computer may produce a web page that can beaccessed by the subject, or another person. In some cases, the web pagemay be a private or encrypted web page accessible only to the subject,and/or only to select individuals (e.g., certain doctors or other healthcare providers). The web page may display information relating to thespecies, other information of interest to or for the subject, or in somecases, the web page may be used to provide a reward to the subject,e.g., for sufficient compliance, or a punishment to the subject, e.g.,for insufficient compliance.

For example, the web page may, in some embodiments, display informationrelating, directly or indirectly, to the species. For example, the webpage may display information regarding compliance or administration ofthe drug or other pharmaceutical substance by the subject, theconcentration of a species in the subject (e.g., of the drug or otherpharmaceutical substance, or a species related to the drug or otherpharmaceutical substance, e.g., a metabolite, a target, a product, aby-product, a marker for a disease treatable by the drug or otherpharmaceutical substance, etc.). As other examples, the web page mayindicate whether the drug (or other pharmaceutical substance) was takenor not, the number of times it was taken by the subject, the degree ofcompliance, the concentration of a species within the subject (measureddirectly or indirectly, e.g., by determining a metabolite within thesubject), the time since the drug (or other pharmaceutical substance)was taken, the time until the next administration of the drug, thenumber of administrations, other health-related information (e.g.,relating to the composition, for example, potential side effects,allergic reactions, interactions with other drugs, etc.), as well aspast histories or one or more of these in some cases, or the like.

In some cases, the web page may display information of interest to orfor the subject. As non-limiting examples, the web page may displayinformation or advertising regarding the drug or other drugs (or othersubstances) of potential interest to or for the subject, health-relatedinformation, links to related web sites, or the like. As specificexamples, the web page may include a link to an on-line “chat” withmedical personnel who can answer questions that the subject may haveregarding the subject's health, or the web page may provide counselingregarding improving compliance of the subject in taking the drug orother pharmaceutical substance.

In another set of embodiments, the web page may use information relatingto the species to produce information, data, probabilities, etc.,relating to the subject. For instance, the web page may indicate that,by successfully complying with a treatment for a certain period of time,the probability of an adverse event has been changed. As a specificexample, the web page may report that, by successfully complying withtreatment over a certain period of time, the probability of a heartattack has decreased by a certain percentage, the probability of anacute attack of a disease has decreased by a certain percentage, thelife expectancy of the subject has increased by a certain amount, etc.

According to one set of embodiments, feedback provided to the subjectmay include a reward, e.g., upon achieving some level of successfulcompliance. For example, the feedback or reward may be provided afterthe subject has taken a drug (or other pharmaceutical substance), afterthe subject has taken the drug a certain number of times, after thesubject has taken the drug for or after a certain period of time, once acertain concentration of a species within subject has been reached, orthe like. In some cases, the reward may be one selected by the user; inother cases, the reward may be determined by another person, e.g., by adoctor or other health care provider, or the reward may bepredetermined. For instance, as discussed below, in one set ofembodiments, a kit may be provided to the subject that includes a drugor other pharmaceutical substance, and a device able to determine thedrug within the skin. The device may, in some cases, be preprogrammed togive a reward when a certain level of compliance by the subject isreached.

The reward may be any suitable reward. In some cases, the reward may beone determinable by the user. In one set of embodiments, the reward maybe provided directly by the device. For instance, the device may displayan image, play a song or music, display a pattern of lights, play amovie or a movie clip, etc., as a suitable reward to the subject. Insome cases, however, the reward may be one that is external to thedevice, i.e., the reward is an “external reward,” which, in the presentinvention, means a material (e.g., financial) and/orencouragement-related reward that is provided to the subject, a sourcethat is not solely the device for obtaining a species and/or sample froma subject. The external source can be, for example, an individual, acomputer, a computing device, or the like, alone or in combination withthe devise. Typically, the source of the external reward is a databasewithin, or is controlled by, a computing device that receivesinformation from the device (directly or via an intermediary) and thendetermines whether a reward should be provided.

As noted, human interaction can also be involved in determining whethera reward should be provided. For example, the reward may be a monetaryreward (e.g., cash, coupons, discounts, gift cards, etc.), physicalmerchandise (e.g., of a predetermined nature, or selectable by the user,etc.), downloadable content (e.g., sound files, game files, pictures,movies, etc.), or the like. As a specific non-limiting example, thereward may be one or more arbitrary “points,” and when a certain numberof points are reached, the subject may be given a reward, or the subjectmay be allowed to choose a reward from a number of potential rewards. Insome cases, the subject may be able to acquire even more points (forexample, for higher levels of compliance, longer periods of compliance,smaller fluctuations in the concentration of a species, etc.) and theability to choose even larger or more valuable rewards. The reward maybe selectable, for example, by access to a suitable web page (e.g., asdiscussed herein), by selecting an item from a physical or an electroniccatalog, or the like. As mentioned, in one set of embodiments, anindicator on the device may be used to indicate that an external rewardis available.

In other embodiments, a punishment may be used instead of and/or inaddition to a reward, e.g., punishment for insufficient compliance.Accordingly, it should be noted that in the discussions herein involving“rewards,” punishments may also be used in other embodiments, instead ofand/or in addition to rewards. For example, the punishment may bemonetary (e.g., a fine), or reduction in points, or simply the absenceof any positive feedback.

In some aspects, the systems described herein may be useful formonitoring intake or effectiveness of any drug or other ingestible orinjectible substance (for which we will use the term “drug” whether thesubstance be pharmaceutical or not). In some cases, the drug (or othersubstance) may be one in which the benefit to the subject taking thedrug is not necessarily immediate or apparent. For example, a drug ableto treat anemia or decrease cholesterol levels may have benefits thatare not immediately felt by the subject (e.g., an increase in red bloodcell count or a decrease in the amount of cholesterol found in theblood). Thus, the subject taking the drug may not be aware of anyimmediate substantial benefit by taking the drug. In many cases, thesubject is discouraged from taking the drug due to the lack of anypositive feedback, i.e., beneficial effects, by taking the drug. In someinstances, this may be compounded by drugs having one or more adverseside effects, i.e., the subject is immediately exposed to adverse sideeffects upon taking the drug, while the beneficial effects of taking thedrug are not immediately apparent. Accordingly, it is a feature ofcertain embodiments of the invention to provide feedback systems forsubjects taking drugs, including but not limited to drugs havingbenefits that are not necessarily immediate or apparent.

In one set of embodiments, the drug (or other substance) is one whosebeneficial effects occur on the time scale of weeks, or drugs whose mainactions do not occur until at least about a day. Examples of such drugsinclude, but are not limited to, drugs that treat anemia, drugs thatlower cholesterol, or drugs that treat high blood pressure, drugs thattreat arthritis, etc. Specific non-limiting examples are discussedbelow. In another set of embodiments, the drug is one whose arequantified using analytical measurements of the subject (or samplestaken from the subject). Often, such drugs have effects cannot be feltby a subject, or cannot be quantified by a subject without analyticalmeasurements beyond a sense of “feeling good.” Examples include, but arenot limited to, drugs that lower cholesterol, drugs that treat anemia,or drugs that treat high blood pressure. In some cases, the drugadministered to the subject is not distinguishable, by the subjectand/or by others, from a placebo without any external equipment (e.g.,blood testing). For instance, on a time scale of a day, 2 days, 3 days,a week, 2 weeks, 3 weeks, 4 weeks, etc., the drug is one that would notbe distinguishable from a placebo by a typical subject taking the drug.For instance, the effects of the drug may take a long time to occur,and/or the symptoms treated by the drug may not be immediatelyidentifiable by the subject (e.g., treatment of mild anemia) in theabsence of any external equipment (e.g., to determine levels ofcirculating blood cells).

In one set of embodiments, the subject may be one that has or is at riskfor high levels of lipids within the blood, for example, cholesterol. Insome cases, for example, the subject may have total blood cholesterollevel of at least about 200 mg/dl, at least about 210 mg/dl, at leastabout 220 mg/dl, etc.; HDL cholesterol levels of less than about 50mg/dl, less than about 40 mg/dl, less than about 30 mg/dl, etc.; and/orLDL cholesterol levels of at least about 130 mg/dl, at least about 140mg/dl, at least about 150 mg/dl, etc. Drugs that a subject may take toreduce or lower cholesterol and/or other lipid levels include, but arenot limited to, statins or HMG-CoA reductase inhibitors (e.g.,mevastatin, atorvastatin, cerivastatin, fluvastatin, lovastatin,pitavastatin, pravastatin, rosuvastatin, simvastatin, and/orcombinations of these and/or other compounds), resins (e.g.,cholestyramine, colestipol, or colesevelam), fibrates (e.g.,gemfibrozil, fenofibrate, clofibrate), or niacin, and these may bedetermined in a subject, e.g., in the blood. For instance, a reward maybe presented to a subject after a certain number or frequency ofpositive results where a satisfactory level of a drug was determinedwithin the subject.

In another set of embodiments, the subject may have or be at risk foranemia, for example, having a decrease in the number of red blood cellsand/or hemoglobin. Drugs useful for treating anemia include, but are notlimited to, iron supplements, folic acid, vitamin B-12, erythropoietinor the like.

The subject may have or be at risk for asthma in yet another set ofembodiments. In some cases, the asthma may include occasional asthmaattacks. Examples of drugs usefully for treating asthma include, but arenot limited to, long-acting bronchodilators such as beta-2-adrenoceptoragonists, salmeterol, formoterol, bambuterol, or albuterol; steroidssuch as fluticasone or budesonide; or combinations of these and/orothers.

The subject, in some embodiments, may have chronic obstructive pulmonarydisease (COPD) or asthma. Examples of potentially useful drugs to treatconditions such as chronic obstructive pulmonary disease or asthmainclude, but are not limited to, beta-2 agonists such as salbutamol,albuterol, terbutaline, salmeterol, or formoterol; anticholinergics suchas ipratropium or tiotropium; corticosteroids such as prednisone,fluticasone, budesonide, mometasone, or beclomethasone; theophylline; orphosphodiesterase-4 antagonists such as roflumilast or cilomilast.Combinations of these and/or other drugs may also be used in some cases.

In still another set of embodiments, the subject may have osteoporosis.The osteoporosis may be treatable by administering drugs such asestrogen, bisphosphonate, calcium, vitamin D, or raloxifene.

In yet another set of embodiments, the subject may have diabetes, andmay need treatment, e.g., with insulin. Glucose may be determined in theblood of the subject to determine the subject's insulin need and/orcompliance with taking insulin at prescribed times.

In some embodiments, the subject may suffer from various chronic heartdiseases. Characteristics determinable to determine if the subject istaking suitable drugs include, but are not limited to, pulse rate, bloodpressure, or blood measurements such as cholesterol, calcium, sodium,potassium, chloride, bicarbonate, blood urea nitrogen (BUN), magnesium,creatinine, or glucose. Rewards such as external rewards may bepresented if certain goals are met for some or all of these.

In another set of embodiments, the subject may suffer from inflammatoryor immune-mediated conditions that are subject to periodic “flare-ups”or acute attacks, and the subject accordingly needs to take drugs tocontrol the frequency of such attacks. Examples include, but are notlimited to, arthritis (e.g., rheumatoid arthritis, osteoarthritis,etc.).

In one set of embodiments, the subject may be one who is trying toreduce addiction, e.g., to nicotine or ethanol. Accordingly, nicotine orethanol may be determined in the subject to determine if or to whatdegree the subject has been able to reduce addiction. Additionally,feedback, e.g., in the form of external rewards, etc., may be useful inproviding a positive environment for the subject to continue efforts atreducing the addiction. Thus, for example, positive feedback or externalrewards may be offered when the substance is not present (or present ina reduced amount) in the subject. In yet another set of embodiments, thesubject may be one who is trying to lose weight. Glucose or other foodcompounds (e.g., triglycerides, free amino acids, other sugars, etc.)may be determined within the subject, and optionally, feedback may beprovided, to the subject based on the determination of such compounds.

In some aspects, the device may be sold together with the drug or otherpharmaceutical substance, e.g., as part of a kit. For example, the kitmay include a drug or other pharmaceutical substance, and a device ableto determine a species within the skin of a subject, e.g., a speciesindicative of the drug or other pharmaceutical substance, as previouslydiscussed. In other embodiments, however, the device may be soldseparately from the drug or other pharmaceutical substance. For example,a doctor or other medical personnel may prescribe a drug (or otherpharmaceutical substance) to a subject, and optionally, the doctor orother medical personnel may prescribe a device of the invention, eitherseparately, or together (e.g., as in a kit). In some cases, however, thedevice itself may be readily available to the subject, e.g., obtainableover-the-counter (OTC) or without a prescription. It should be notedthat even if the drug itself requires a prescription, if the device issold separately (without the drug), it need not necessarily also requirea prescription to be purchased. Further examples of kits are discussedin detail below.

As previously discussed, in one set of embodiments, the device is ableto deliver and/or withdraw fluid from the skin of a subject, or othermucosal surface, as well as methods of use thereof. In some cases, thedevice may pierce the skin of the subject, and fluid can then bedelivered and or withdrawn from the subject. The subject is usuallyhuman, although non-human subjects may be used in certain instances, forinstance, other mammals such as a dog, a cat, a horse, a rabbit, a cow,a pig, a sheep, a goat, a rat (e.g., Rattus norvegicus), a mouse (e.g.,Mus musculus), a guinea pig, a hamster, a primate (e.g., a monkey, achimpanzee, a baboon, an ape, a gorilla, etc.), or the like. If a fluidis withdrawn from the subject, the withdrawn fluid may be any suitablebodily fluid. In one set of embodiments, essentially any body fluid canbe used, such as interstitial fluid, other skin-associated material,mucosal material or fluid, whole blood, perspiration and saliva, plasma,or any other bodily fluid.

Non-limiting examples of various devices of the invention are shown inFIG. 1. In FIG. 1A, device 90 is used for withdrawing a fluid from asubject when the device is placed on the skin of a subject. Device 90includes sensor 95 and fluid transporter 92, e.g., one or more needlesor microneedles, etc., as discussed herein. In fluidic communicationwith fluid transporter 92 via fluidic channel 99 is sensing chamber 97.In some cases, fluid may be withdrawn using fluid transporter 92 by avacuum, for example, a self-contained vacuum contained within device 90.In one embodiment, sensing chamber 97 may contain agents such asparticles, enzymes, dyes, etc., for analyzing bodily fluids, such asinterstitial fluid or blood. Optionally, device 90 also contains adisplay 94 and associated electronics, processors, batteries or otherpower supplies 93, etc., which may be used to display sensor readingsobtained via sensor 95. In addition, device 90 may also optionallycontain memory 98 for receiving and storing one or more of sensorreadings, calibration data and software for operating a processingelement, and transmitters for transmitting a signal indicative of sensor95 to a receiver, etc. Electronics 93 may include circuitry forreceiving and filtering, amplifying or otherwise processing signals fromsensor 95, one or more processing elements (e.g., microprocessors,application-specific integrated circuits or other types of informationprocessing hardware) for deriving information including parameter valuesform the sensor signals, and circuitry for driving the display.

In the example shown in FIG. 1A, device 90 may contain a vacuum source(not shown) that is self-contained within device 90, although in otherembodiments, the vacuum source may be external to device 90. (In stillother instances, other systems may be used to deliver and/or withdrawfluid from the skin and/or beneath the skin, as is discussed herein.) Inone embodiment, after the device is placed on the skin of a subject, theskin may be drawn upward into a recess containing fluid transporter 92,for example, upon exposure to the vacuum source. Access to the vacuumsource may be controlled by any suitable method, e.g., by piercing aseal or a septum; by opening a valve or moving a gate, etc. Forinstance, upon activation of device 90, e.g., by the subject, remotely,automatically, etc., the vacuum source may be put into fluidiccommunication with the recess such that skin is drawn into the recesscontaining fluid transporter 92 due to the vacuum. Skin drawn into therecess may come into contact with fluid transporter 92 (e.g., solid orhollow needles or microneedles), which may, in some cases, pierce theskin and allow a fluid to be delivered to and/or withdrawn from the skinand/or beneath the skin. In another embodiment, fluid transporter 92 maybe actuated and moved downward to come into contact with the skin, andoptionally retracted after use.

Another non-limiting example of a device is shown in FIG. 1B. Thisfigure illustrates a device useful for delivering a fluid to thesubject. Device 90 in this figure includes fluid transporter 92, e.g.,one or more needles or microneedles, etc., as discussed herein. Influidic communication with fluid transporter 92 via fluidic channel 99is chamber 97, which may contain a drug or other substance to bedelivered to the subject. In some cases, fluid may be delivered with apressure controller, and/or withdrawn using fluid transporter 92 by avacuum, for example, a self-contained vacuum contained within device 90.For instance, upon creating a vacuum, skin may be drawn up towards fluidtransporter 92, and fluid transporter 92 may pierce the skin. Fluid fromchamber 97 can then be delivered into or through the skin and/orwithdrawn therefrom, through fluid channel 99 and fluid transporter 92.Optionally, device 90 also contains a display 94 (showing “100” in thisexample) or other device indicator, and associated electronics 93,batteries or other power supplies, etc., which may be used controldelivery of fluid to or beneath the skin. In addition, device 90 mayalso optionally contain memory 98, transmitters for transmitting asignal indicative of device 90 or fluid delivery to a receiver, etc.

Yet another non-limiting example of a device according to someembodiments of the invention is shown in FIG. 2. FIG. 2A illustrates aview of the device (with the cover removed), while FIG. 2B schematicallyillustrates the device in cross-section. In FIG. 2B, device 50 includesa needle 52 contained within a recess 55. Needle 52 may be solid orhollow, depending on the embodiment, and there may be one or more thanone present. Device 50 also includes a self-contained vacuum chamber 60,which wraps around the central portion of the device where needle 52 andrecess 55 are located. A channel 62 connects vacuum chamber 60 withrecess 55, separated by a foil or a membrane 67. Also shown in device 50is button 58. When pushed, button 58 breaks foil 67, thereby connectingvacuum chamber 50 with recess 55, creating a vacuum in recess 55. Thevacuum may be used, for example, to draw skin into recess 55, preferablysuch that it contacts needle 52, which then pierces the surface of theskin, thereby gaining access to an internal fluid such as blood orinterstitial fluid. The fluid may be controlled, for example, bycontrolling the size of needle 52, and thereby the depth of penetration.For example, the penetration may be limited to the epidermis, e.g., tocollect interstitial fluid, or to the dermis, e.g., to collect blood. Insome cases, the vacuum may also be used to at least partially securedevice 50 on the surface of the skin, and/or to assist in the withdrawalof fluid from the skin and/or beneath the skin. For instance, fluid mayflow into channel 62 under action of the vacuum, and optionally tosensor 61, e.g., for detection of an analyte contained within the fluid.For instance, sensor 61 may produce a color change if an analyte ispresent, or otherwise produce a detectable signal.

Other components may be added to the example of the device illustratedin FIG. 2, in some embodiments of the invention. For example, device 50may contain a cover, displays, ports, transmitters, sensors, A/Dconverters, chambers such as microfluidic chambers, channels such asmicrofluidic channels, and/or various electronics, e.g., to control ormonitor fluid transport into or out of device 50, to determine ananalyte present within a fluid delivered to and/or withdrawn from theskin and/or beneath the skin, to determine the status of the device, toreport or transmit information regarding the device and/or analytes, orthe like, as is discussed in more detail herein. As another example,device 50 may contain an adhesive, e.g., on surface 54, for adhesion ofthe device to the skin.

Yet another non-limiting example is illustrated with reference to FIG.2C. In this example, device 500 includes a support structure 501, and anassociated fluid transporter system 503. Fluid transporter system 503includes one or more needles or microneedles 505, although other fluidtransporters as discussed herein may also be used. Also shown in FIG. 2Cis sensor 510, connected via channels 511 to recess 508 containing oneor more needles or microneedles 505. Chamber 513 may be a self-containedvacuum chamber, and chamber 513 may be in fluidic communication withrecess 508 via channel 511, for example, as controlled by a controlleror an actuator (not shown). In this figure, device 500 also containsdisplay 525, which is connected to sensor 510 via electrical connection522. As an example of use of device 500, when fluid is drawn from theskin and/or beneath the skin (e.g., blood, interstitial fluid, etc.),the fluid may flow through channel 511 to be determined by sensor 510,e.g., due to action of the vacuum from vacuum chamber 513. In somecases, the vacuum is used, for example, to draw skin into recess 508,preferably such that it contacts one or more needles or microneedles 505and pierces the surface of the skin to gain access to a fluid internalof the subject, such as blood or interstitial fluid, etc. The fluid maybe controlled, for example, by controlling the size of needle 52, andthereby the depth of penetration. For example, the penetration may belimited to the epidermis, e.g., to collect interstitial fluid, or to thedermis, e.g., to collect blood. Upon determination of the fluid and/oran analyte present or suspected to be present within the fluid, amicroprocessor or other controller may display on display 525 a suitablesignal. As is discussed below, a display is shown in this figure by wayof example only; in other embodiments, no display may be present, orother signals may be used, for example, lights, smell, sound, feel,taste, or the like.

In some cases, more than one fluid transporter system may be presentwithin the device. For instance, the device may be able to be usedrepeatedly, and/or the device may be able to deliver and/or withdrawfluid at more than one location on a subject, e.g., sequentially and/orsimultaneously. As a specific example, in one set of embodiments, thedevice may include one or more needles, for instance, arranged in anarray. In some embodiments, one or more of the needles may be amicroneedle. In some cases, the device may be able to simultaneouslydeliver to and withdraw fluid from a subject. A non-limiting example ofa device having more than one fluid transporter system is illustratedwith reference to FIG. 2E. In this example, device 500 contains aplurality of structures such as those described herein for deliveringand/or withdrawing fluid from a subject, e.g., to and/or from the skinand/or beneath the skin of the subject. For example, device 500 in thisexample contains 3 such units, although any number of units are possiblein other embodiments. In this example, device 500 contains three suchfluid transporter systems 575. Each of these fluid transporter systemsmay independently have the same or different structures, depending onthe particular application, and they may have structures such as thosedescribed herein.

In some embodiments, the device may take the form of a skin “patch.”Typically, a skin patch includes one or more layers of material that areadhered to the surface of the skin, and can be applied by the subject oranother person. In certain embodiments, layers or portions of the skinpatch may be removed, leaving other layers or portions behind on theskin. Often, the skin patch lacks an external power source, although thevarious layers of the patch may contain various chemicals, such asdrugs, therapeutic agents, diagnostic agents, reaction entities, etc. Insome cases, the skin patch may also include mechanical elements as well,for example, a cutter such as is discussed herein.

As another example, the device may be a handheld device that is appliedto the surface of the skin of a subject. In some cases, however, thedevice may be sufficiently small or portable that the subject canself-administer the device. In certain embodiments, the device may alsobe powered. In some instances, the device may be applied to the surfaceof the skin, and is not inserted into the skin. In other embodiments,however, at least a portion of the device may be inserted into the skin,for example, mechanically. For example, in one embodiment, the devicemay include a cutter, such as a hypodermic needle, a knife blade, apiercing element (e.g., a solid or hollow needle), or the like, asdiscussed herein.

In some cases, the device may be designed such that portions of thedevice are separable. For example, a first portion of the device may beremoved from the surface of the skin, leaving other portions of thedevice behind on the skin. In one embodiment, a stop may also beincluded to prevent or control the depth to which the cutter or otherdevice inserts into the skin, e.g., to control penetration to theepidermis, dermis, etc.

Accordingly, as described herein, devices of the invention can besingle-stage or multi-stage in some cases. That is, the device candefine a single unit that includes one or more components integrallyconnected to each other which cannot readily be removed from each otherby a user, or the device can include one or more components which aredesigned to be and can readily be removed from each other. As anon-limiting example of the latter, a two-stage patch can be providedfor application to the skin of a subject. The patch can include a firststage designed to reside proximate the skin of the subject for theduration of the analysis, which might include an analysis region, areservoir or other material for creating vacuum or otherwise promotingthe flow of fluid or other materials relative to the analysis region,one or more needles or microneedles, or other fluid transporters, toaccess interstitial fluid via suction blister or without a suctionblister or the like.

A second stage or portion of the device can be provided that caninitiate operation of the device. For example, a two stage device can beapplied to the skin of a subject. A button, switch, or other actuatorassociated with the second portion of the device can be activated by thesubject to cause insertion of one or more needles or microneedles orother fluid transporters to the skin of the subject, or the like. Then,the second stage can be removed, e.g., by the subject or another person,and the first stage can remain on the skin of the subject to facilitateanalysis. In another arrangement, a two-stage device can be providedwhere the first stage includes visualization or other signal-producingcomponents and the second stage includes components necessary tofacilitate the analysis, e.g., the second stage can include allcomponents necessary to access bodily fluid, transport the fluid (ifnecessary) to a site of analysis, and the like, and that stage can beremoved, leaving only a visualization stage for the subject or anotherentity to view or otherwise analyze as described herein.

Any or all of the arrangements described herein can be providedproximate a subject, for example on or proximate the skin of a subject,in various aspects. Activation of the devices can be carried out in avariety of ways, e.g., as described herein. For example, an on-skindevice can be in the form of a patch or the like, optionally includingmultiple layers for activation, sensing, fluid flow, etc. In oneembodiment, a patch or a device can be applied to a subject and a regionof the patch or device activated (e.g., pushed, pressed, or tapped by auser) to inject a needle or a microneedle, or other fluid transporter,so as to access interstitial fluid or blood. The same or a differentactivation action, e.g., tapping or pushing action, can activate avacuum source, open and/or close one or more of a variety of valves, orthe like. The device can be a simple one in which it is applied to theskin and operates automatically (where e.g., application of the deviceto the skin allows access to interstitial fluid or blood and deliversand/or withdraws fluid such as blood or interstitial fluid, e.g., intoan analysis region) or the patch or other device can be applied to theskin and one tapping or other activation can cause fluid to flow throughadministration of one or more needles or microneedles (or other fluidtransporter), opening of a valve, activation of vacuum, or anycombination thereof. Any number of activation protocols can be carriedout by a user repeatedly pushing, tapping, etc. a location orselectively, sequentially, and/or periodically activating a variety ofswitches (e.g., tapping regions of a patch). With this description,those of ordinary skill in the art can understand how any of the assaysdescribed above with respect to one and two can be facilitated.

In another arrangement, activation of one or more needles ormicroneedles, creation of suction blisters, opening and/or closing ofvalves, and other techniques to facilitate delivery and/or withdraw of afluid can be carried out electronically or in other manners facilitatedby the subject or by an outside controlling entity (e.g., another userof the device). For example, a device or patch can be provided proximatethe skin of a subject and a radio frequency, electromagnetic, or othersignal can be provided by a nearby controller or a distant source toactivate any of the needles, fluid transporters, blister devices,valves, or other components of the devices described so that anydelivery and/or withdrawal of a fluid, and/or any assay or assays can becarried out as desired.

As discussed, various devices of the invention include various systemsand methods for delivering to and/or withdrawing fluid from the skinand/or beneath the skin of the subject, according to certainembodiments. For instance, the device may comprise a needle such as ahypodermic needle, a vacuum source, a hygroscopic agent, or the like.Non-limiting examples of suitable delivery techniques include, but arenot limited to, injection (e.g., using needles such as hypodermicneedles) or a jet injector, such as those discussed below. For instance,in one embodiment, the fluid is delivered and/or withdrawn manually,e.g., by manipulating a plunger on a syringe. In another embodiment, thefluid can be delivered to and/or withdrawn from the skin and/or beneaththe skin mechanically or automatically, e.g., using a piston pump or thelike. Fluid may also be withdrawn using vacuums such as those discussedherein. For example, vacuum may be applied to a conduit, such as aneedle, in fluidic communication with a bodily fluid in order to draw upat least a portion of the fluid from the skin. In yet anotherembodiment, fluid is withdrawn using capillary action (e.g., using amicrofluidic channel or a hypodermic needle having a suitably narrowinner diameter). In still another embodiment, pressure may be applied toforce fluid out of the needle.

In some cases, as discussed below, pooled regions of fluid may becreated in the skin for facilitating delivery to and/or withdrawal offluid from the skin. For instance, fluid may be pooled within the skinthat is drawn from the surrounding dermal and/or epidermal layers withinthe skin. The fluid may include interstitial fluid or blood. In othercases, however, no pooling is necessary for the delivery to and/orwithdraw of fluid from the skin.

For instance, fluids withdrawn from the skin and/or from beneath theskin of the subject will often contain various analytes from within thebody that are important for diagnostic purposes, for example, markersfor various disease states, such as glucose (e.g., for diabetics); otherexample analytes include ions such as sodium, potassium, chloride,calcium, magnesium, and/or bicarbonate (e.g., to determine dehydration);gases such as carbon dioxide or oxygen; H⁺ (i.e., pH); metabolites suchas urea, blood urea nitrogen or creatinine; hormones such as estradiol,estrone, progesterone, progestin, testosterone, androstenedione, etc.(e.g., to determine pregnancy, illicit drug use, or the like); orcholesterol. Other examples include insulin, or hormone levels. Stillother analytes include, but not limited to, high-density lipoprotein(“HDL”), low-density lipoprotein (“LDL”), albumin, alanine transaminase(“ALT”), aspartate transaminase (“AST”), alkaline phosphatase (“ALP”),bilirubin, lactate dehydrogenase, etc. (e.g., for liver function tests);luteinizing hormone or beta-human chorionic gonadotrophin (hCG) (e.g.,for fertility tests); prothrombin (e.g., for coagulation tests);troponin, BNT or B-type natriuretic peptide, etc., (e.g., as cardiacmarkers); infectious disease markers for the flu, respiratory syncytialvirus or RSV, etc.; or the like.

As discussed herein, certain embodiments of the present invention aregenerally directed at methods for withdrawing fluids from the body, andoptionally determining one or more analytes within the withdrawn fluid.Thus, in some embodiments, at least a portion of the fluid may bestored, and/or analyzed to determine one or more analytes, e.g., amarker for a disease state, or the like, e.g., to allow for themonitoring of the state of disease in a subject. The fluid withdrawnfrom the skin and/or beneath the skin may be subjected to such uses,and/or one or more materials previously delivered to the skin may besubject to such uses.

In other embodiments, fluid may be delivered to the skin of the subject,and such fluids may contain materials useful for delivery, e.g., formingat least a portion of the fluid, dissolved within the fluid, carried bythe fluid (e.g., suspended or dispersed), or the like. Examples ofsuitable materials include, but are not limited to, particles such asmicroparticles or nanoparticles, a chemical, a drug or a pharmaceuticalsubstance, a diagnostic agent, a carrier, or the like.

As used herein, the term “fluid” generally refers to a substance thattends to flow and to conform to the outline of its container. Typically,fluids are materials that are unable to withstand a static shear stress,and when a shear stress is applied, the fluid experiences a continuingand permanent distortion. The fluid may have any suitable viscosity thatpermits at least some flow of the fluid. Non-limiting examples of fluidsinclude liquids and gases, but may also include free-flowing solidparticles, viscoelastic fluids, and the like. For example, the fluid mayinclude a flowable matrix or a gel, e.g., formed from biodegradableand/or biocompatible material such as polylactic acid, polyglycolicacid, poly(lactic-co-glycolic acid), etc., or other similar materials.

In some cases, fluids or other materials delivered to the subject may beused for indication of a past, present and/or future condition of thesubject. Thus, the condition of the subject to be determined may be onethat is currently existing in the subject, and/or one that is notcurrently existing, but the subject is susceptible or otherwise is at anincreased risk to that condition. The condition may be a medicalcondition, e.g., diabetes or cancer, or other physiological conditions,such as dehydration, pregnancy, illicit drug use, or the like.Additional non-limiting examples are discussed herein. In one set ofembodiments, the materials may include a diagnostic agent, for example,one which can determine an analyte within the subject, e.g., one that isa marker for a disease state. As a specific non-limiting example, fluiddelivered to the skin and/or beneath the skin of a subject may include aparticle including an antibody directed at a marker produced by abacterium.

In other cases, however, fluids or other materials delivered to thesubject may be used to determine conditions that are external to thesubject. For example, the fluids or other materials may contain reactionentities able to recognize pathogens or other environmental conditionssurrounding the subject, for example, an antibody able to recognize anexternal pathogen (or pathogen marker). As a specific example, thepathogen may be anthrax and the antibody may be an antibody to anthraxspores. As another example, the pathogen may be a Plasmodia (somespecies of which causes malaria) and the antibody may be an antibodythat recognizes the Plasmodia.

According to one set of embodiments, many devices as discussed hereinuse various techniques for delivering to and/or withdrawing fluid fromthe skin and/or from beneath the skin, for example, in connection withfluid transporters, substance transfer components, microinsertionobjects, or the like. For example, one or more needles and/ormicroneedles, a hygroscopic agent, a cutter or other piercing element,an electrically-assisted system, or the like may be used in conjunctionwith any device described herein. Additional examples of such techniquesare described herein and/or in the applications incorporated herein. Itis to be understood that, generally, fluids may be delivered and/orwithdrawn in a variety of ways, and various systems and methods fordelivering to and/or withdrawing fluid from the skin and/or beneath theskin are discussed below and/or in the applications incorporated herein.In one set of embodiments, techniques for piercing or altering thesurface of the skin to transport a fluid are discussed, for example,using a needle such as a hypodermic needle or one or more microneedles,chemicals applied to the skin (e.g., penetration enhancers), or jetinjectors or other techniques such as those discussed below.

As an example, in one method, a needle such as a hypodermic needle canbe used to deliver and/or withdraw fluid to or from the skin and/orbeneath the skin. Hypodermic needles are well-known to those of ordinaryskill in the art, and can be obtained commercially with a range ofneedle gauges. For example, the needle may be in the 20-30 gauge range,or the needle may be 32 gauge, 33 gauge, 34 gauge, etc.

If needles are present, there may be one or more needles, the needlesmay be of any suitable size and length, and the needles may each besolid or hollow. The needles may have any suitable cross-section (e.g.,normal or perpendicular to the direction of penetration), for example,circular, square, oval, elliptical, rectangular, rounded rectangle,triangular, polygonal, hexagonal, irregular, etc. For example, theneedle may have a length of less than about 5 mm, less than about 4 mm,less than about 3 mm, less than about 2 mm, less than about 1 mm, lessthan about 800 micrometers, less than 600 micrometers, less than 500micrometers, less than 400 micrometers, less than about 300 micrometers,less than about 200 micrometers, less than about 175 micrometers, lessthan about 150 micrometers, less than about 125 micrometers, less thanabout 100 micrometers, less than about 75 micrometers, less than about50 micrometers, less than about 10 micrometers, etc. The needle may alsohave a largest cross-sectional dimension of less than about 5 mm, lessthan about 4 mm, less than about 3 mm, less than about 2 mm, less thanabout 1 mm, less than about 800 micrometers, less than 600 micrometers,less than 500 micrometers, less than 400 micrometers, less than about300 micrometers, less than about 200 micrometers, less than about 175micrometers, less than about 150 micrometers, less than about 125micrometers, less than about 100 micrometers, less than about 75micrometers, less than about 50 micrometers, less than about 10micrometers, etc. For example, in one embodiment, the needle may have arectangular cross section having dimensions of 175 micrometers by 50micrometers. In one set of embodiments, the needle may have an aspectratio of length to largest cross-sectional dimension of at least about2:1, at least about 3:1, at least about 4:1, at least 5:1, at leastabout 7:1, at least about 10:1, at least about 15:1, at least about20:1, at least about 25:1, at least about 30:1, etc.

In one embodiment, the needle is a microneedle. Typically, a microneedlewill have an average cross-sectional dimension (e.g., diameter) of lessthan about a millimeter. It should be understood that references to“needle” or “microneedle” as discussed herein are by way of example andease of presentation only, and that in any of the various embodiments,more than one needle and/or microneedle may be present.

As an example, microneedles such as those disclosed in U.S. Pat. No.6,334,856, issued Jan. 1, 2002, titled “Microneedle Devices and Methodsof Manufacture and Use Thereof,” by Allen, et al., may be used todeliver to and/or withdraw fluids (or other materials) from a subject.The microneedles may be hollow or solid, and may be formed from anysuitable material, e.g., metals, ceramics, semiconductors, organics,polymers, and/or composites. Examples include, but are not limited to,medical grade stainless steel, titanium, nickel, iron, gold, tin,chromium, copper, alloys of these or other metals, silicon, silicondioxide, and polymers, including polymers of hydroxy acids such aslactic acid and glycolic acid polylactide, polyglycolide,polylactide-co-glycolide, and copolymers with polyethylene glycol,polyanhydrides, polyorthoesters, polyurethanes, polybutyric acid,polyvaleric acid, polylactide-co-caprolactone, polycarbonate,polymethacrylic acid, polyethylenevinyl acetate, polytetrafluorethylene,polymethyl methacrylate, polyacrylic acid, or polyesters.

In some cases, more than one needle or microneedle may be used. Forexample, arrays of needles or microneedles may be used, and the needlesor microneedles may be arranged in the array in any suitableconfiguration, e.g., periodic, random, etc. In some cases, the array mayhave 3 or more, 4 or more, 5 or more, 10 or more, 15 or more, 20 ormore, 35 or more, 50 or more, 100 or more, or any other suitable numberof needles or microneedles. In some embodiments, the device may have atleast 3 but no more than 5 needles or microneedles (or other fluidtransporters), at least 6 but no more than 10 needles or microneedles,or at least 11 but no more than 20 needles or microneedles. Typically, amicroneedle will have an average cross-sectional dimension (e.g.,diameter) of less than about a micron.

Those of ordinary skill in the art can arrange needles relative to theskin for these purposes including, in one embodiment, introducingneedles into the skin at an angle, relative to the skin's surface, otherthan 90°, i.e., to introduce a needle or needles into the skin in aslanting fashion so as to limit the depth of penetration. In anotherembodiment, however, the needles may enter the skin at approximately90°.

In some cases, the needles (or microneedles) may be present in an arrayselected such that the density of needles within the array is betweenabout 0.5 needles/mm² and about 10 needles/mm², and in some cases, thedensity may be between about 0.6 needles/mm² and about 5 needles/mm²,between about 0.8 needles/mm² and about 3 needles/mm², between about 1needles/mm² and about 2.5 needles/mm², or the like. In some cases, theneedles may be positioned within the array such that no two needles arecloser than about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about0.6 mm, about 0.5 mm, about 0.4 mm, about 0.3 mm, about 0.2 mm, about0.1 mm, about 0.05 mm, about 0.03 mm, about 0.01 mm, etc.

In another set of embodiments, the needles (or microneedles) may bechosen such that the area of the needles (determined by determining thearea of penetration or perforation on the surface of the skin of thesubject by the needles) allows for adequate flow of fluid to or from theskin and/or beneath the skin of the subject. The needles may be chosento have smaller or larger areas (or smaller or large diameters), so longas the area of contact for the needles to the skin is sufficient toallow adequate blood flow from the skin of the subject to the device.For example, in certain embodiments, the needles may be selected to havea combined skin-penetration area of at least about 500 nm², at leastabout 1,000 nm², at least about 3,000 nm², at least about 10,000 nm², atleast about 30,000 nm², at least about 100,000 nm², at least about300,000 nm², at least about 1 microns², at least about 3 microns², atleast about 10 microns², at least about 30 microns², at least about 100microns², at least about 300 microns², at least about 500 microns², atleast about 1,000 microns², at least about 2,000 microns², at leastabout 2,500 microns², at least about 3,000 microns², at least about5,000 microns², at least about 8,000 microns², at least about 10,000microns², at least about 35,000 microns², at least about 100,000microns², at least about 300,000 microns², at least about 500,000microns², at least about 800,000 microns², at least about 8,000,000microns², etc., depending on the application.

The needles or microneedles may have any suitable length, and the lengthmay be, in some cases, dependent on the application. For example,needles designed to only penetrate the epidermis may be shorter thanneedles designed to also penetrate the dermis, or to extend beneath thedermis or the skin. In certain embodiments, the needles or microneedlesmay have a maximum penetration into the skin of no more than about 3 mm,no more than about 2 mm, no more than about 1.75 mm, no more than about1.5 mm, no more than about 1.25 mm, no more than about 1 mm, no morethan about 900 microns, no more than about 800 microns, no more thanabout 750 microns, no more than about 600 microns, no more than about500 microns, no more than about 400 microns, no more than about 300microns, no more than about 200 microns, no more than about 175micrometers, no more than about 150 micrometers, no more than about 125micrometers, no more than about 100 micrometers, no more than about 75micrometers, no more than about 50 micrometers, etc. In certainembodiments, the needles or microneedles may be selected so as to have amaximum penetration into the skin of at least about 50 micrometers, atleast about 100 micrometers, at least about 300 micrometers, at leastabout 500 micrometers, at least about 1 mm, at least about 2 mm, atleast about 3 mm, etc.

In one set of embodiments, the needles (or microneedles) may be coated.For example, the needles may be coated with a substance that isdelivered when the needles are inserted into the skin. For instance, thecoating may comprise heparin, an anticoagulant, an anti-inflammatorycompound, an analgesic, an anti-histamine compound, etc. to assist withthe flow of blood from the skin of the subject, or the coating maycomprise a drug or other pharmaceutical substance such as thosedescribed herein. The drug or other pharmaceutical substance may be oneused for localized delivery (e.g., of or proximate the region to whichthe coated needles or microneedles are applied), and/or the drug orother pharmaceutical substance may be one intended for systemic deliverywithin the subject.

In one embodiment, the fluid is delivered and/or withdrawn manually,e.g., by manipulating a plunger on a syringe. In another embodiment, thefluid can be delivered to and/or withdrawn from the skin and/or beneaththe skin mechanically or automatically, e.g., using a piston pump or thelike. Fluid may also be withdrawn using vacuums such as those discussedherein. For example, vacuum may be applied to a conduit, such as aneedle, in fluidic communication with a bodily fluid in order to draw upat least a portion of the fluid from the skin. In yet anotherembodiment, fluid is withdrawn using capillary action (e.g., using amicrofluidic channel or hypodermic needle having a suitably narrow innerdiameter). In still another embodiment, pressure may be applied to forcefluid out of the needle.

As still another example, pressurized fluids may be used to deliverfluids or other materials into and/or through the skin, for instance,using a jet injector or a “hypospray.” Typically, such devices produce ahigh-pressure “jet” of liquid or powder (e.g., a biocompatible liquid,such as saline) that drives material into the skin, and the depth ofpenetration may be controlled, for instance, by controlling the pressureof the jet. The pressure may come from any suitable source, e.g., astandard gas cylinder or a gas cartridge. A non-limiting example of sucha device can be seen in U.S. Pat. No. 4,103,684, issued Aug. 1, 1978,titled “Hydraulically Powered Hypodermic Injector with Adapters forReducing and Increasing Fluid Injection Force,” by Ismach.Pressurization of the liquid may be achieved, for example, usingcompressed air or gas, for instance, from a gas cylinder or a gascartridge.

In some embodiments, fluid may be withdrawn using a hygroscopic agentapplied to the surface of the skin or proximate the skin. For example, adevice as described herein may contain a hygroscopic agent. In somecases, pressure may be applied to drive the hygroscopic agent into theskin. Hygroscopic agents typically are able to attract water from thesurrounding environment, for instance, through absorption or adsorption.Non-limiting examples of hygroscopic agents include sugar, honey,glycerol, ethanol, methanol, sulfuric acid, methamphetamine, iodine,many chloride and hydroxide salts, and a variety of other substances.Other examples include, but are not limited to, zinc chloride, calciumchloride, potassium hydroxide, or sodium hydroxide. In some cases, asuitable hygroscopic agent may be chosen based on its physical orreactive properties, e.g., inertness or biocompatibility towards theskin of the subject, depending on the application.

In some embodiments, the device may comprise a cutterable to cut orpierce the surface of the skin. The cutter may comprise any mechanismable to create a path through which fluids may be delivered to and/orwithdrawn from the skin and/or beneath the skin. For example, the cuttermay comprise a hypodermic needle, a blade (e.g., a knife blade, aserrated blade, etc.), a piercing element (e.g., a lancet or a solid ora hollow needle), or the like, which can be applied to the skin tocreate a suitable conduit for the delivery and/or withdrawal of fluidfrom the skin and/or from beneath the skin. In one embodiment, a cutteris used to create such a pathway and removed, then fluid may bedelivered and/or withdrawn via this pathway. In another embodiment, thecutter remains in place within the skin, and fluid may be deliveredand/or withdrawn through a conduit within the cutter.

In some embodiments, fluid may be delivered and/or withdrawn using anelectric charge. For example, reverse iontophoresis may be used. Withoutintending to be bound by any theory, reverse iontophoresis uses a smallelectric current to drive charged and highly polar compounds across theskin. Since the skin is negatively charged at physiologic pH, it acts asa permselective membrane to cations, and the passage of counterionsacross the skin induces an electroosmotic solvent flow that may carryneutral molecules in the anode-to-cathode direction. Components in thesolvent flow may be analyzed as described elsewhere herein. In someinstances, a reverse iontophoresis apparatus may comprise an anode celland a cathode cell, each in contact with the skin. The anode cell may befilled, for example, with an aqueous buffer solution (i.e., aqueous Trisbuffer) having a pH greater than 4 and an electrolyte (i.e. sodiumchloride). The cathode cell can be filled with aqueous buffer. As oneexample, a first electrode (e.g., an anode) can be inserted into theanode cell and a second electrode (e.g., a cathode) can be inserted inthe cathode cell. In some embodiments, the electrodes are not in directcontact with the skin.

A current may be applied to induce reverse iontophoresis, therebywithdrawing a fluid from the skin. The current applied may be, forexample, greater than 0.01 mA, greater than 0.3 mA, greater than 0.1 mA,greater than 0.3 mA, greater than 0.5 mA, or greater than 1 mA. Itshould be understood that currents outside these ranges may be used aswell. The current may be applied for a set period of time. For example,the current may be applied for greater than 30 seconds, greater than 1minute, greater than 5 minutes, greater than 30 minutes, greater than 1hour, greater than 2 hours, or greater than 5 hours. It should beunderstood that times outside these ranges may be used as well.

In one set of embodiments, the device may comprise an apparatus forablating the skin. Without wishing to be bound by any theory, it isbelieved that ablation comprises removing a microscopic patch of stratumcorneum (i.e., ablation forms a micropore), thus allowing access tobodily fluids. In some cases, thermal, radiofrequency, and/or laserenergy may be used for ablation. In some instances, thermal ablation maybe applied using a heating element. Radiofrequency ablation may becarried out using a frequency and energy capable of heating water and/ortissue. A laser may also be used to irradiate a location on the skin toremove a portion. In some embodiments, the heat may be applied in pulsessuch that a steep temperature gradient exists essentially perpendicularto the surface of the skin. For example, a temperature of at least 100°C., at least 200° C., at least 300° C., or at least 400° C. may beapplied for less than 1 second, less than 0.1 seconds, less than 0.01seconds, less than 0.005 seconds, or less than 0.001 seconds.

In some embodiments, the device may comprise a mechanism for taking asolid sample of tissue. For example, a solid tissue sample may beacquired by methods such as scraping the skin or cutting out a portion.Scraping may comprises a reciprocating action whereby an instrument isscraped along the surface of the skin in two or more directions.Scraping can also be accomplished by a rotating action, for exampleparallel to the surface of the skin and in one direction (i.e., with aroller drum) or parallel to the surface of the skin and in a circularmanner (i.e., with a drilling instrument). A cutting mechanism maycomprise a blade capable of making one or more incisions and a mechanismfor removing a portion of tissue (i.e., by suction or mechanicallypicking up) or may use a pincer mechanism for cutting out a portion oftissue. A cutting mechanism may also function by a coring action. Forexample, a hollow cylindrical device can be penetrated into the skinsuch that a cylindrical core of tissue may be removed. A solid samplemay be analyzed directly or may be liquefied prior to analysis.Liquefaction can comprise treatment with organic solvents, enzymaticsolutions, etc.

The device may also contain, in some aspects, a vacuum source. In somecases, the vacuum source is one that is self-contained within thedevice, i.e., the device need not be connected to an external vacuumsource (e.g., a house vacuum) during use of the device to withdraw bloodor interstitial fluid from the skin and/or from beneath the skin. Forexample, in one set of embodiments, the vacuum source may include avacuum chamber having a pressure less than atmospheric pressure beforeblood (or other fluid) is withdrawn into the device, i.e., the vacuumchamber is at a “negative pressure” (that is, negative relative toatmospheric pressure) or a “vacuum pressure” (or just having a“vacuum”). For example, the vacuum in the vacuum chamber may be at leastabout 50 mmHg, at least about 100 mmHg, at least about 150 mmHg, atleast about 200 mmHg, at least about 250 mmHg, at least about 300 mmHg,at least about 350 mmHg, at least about 400 mmHg, at least about 450mmHg, at least about 500 mmHg, at least 550 mmHg, at least 600 mmHg, atleast 650 mmHg, at least about 700 mmHg, or at least about 750 mmHg,i.e., below atmospheric pressure. Thus, the pressure within the vacuumis at a “reduced pressure” relative to atmospheric pressure, e.g., thevacuum chamber is a reduced pressure chamber. However, in otherembodiments, it should be understood that other pressures may be usedand/or that different methods may be used to produce other pressures(greater than or less than atmospheric pressure). As non-limitingexamples, an external vacuum or a mechanical device may be used as thevacuum source; various additional examples are discussed in detailherein.

In some embodiments, fluids may be withdrawn from the skin and/orbeneath the skin using a vacuum. The vacuum may be an external vacuumsource, and/or the vacuum source may be self-contained within thedevice. For example, vacuums of at least about 50 mmHg, at least about100 mmHg, at least about 150 mmHg, at least about 200 mmHg, at leastabout 250 mmHg, at least about 300 mmHg, at least about 350 mmHg, atleast about 400 mmHg, at least about 450 mmHg, at least about 500 mmHg,at least 550 mmHg, at least 600 mmHg, at least 650 mmHg, at least about700 mmHg, or at least about 750 mmHg may be applied to the skin. As usedherein, “vacuum” refers to pressures that are below atmosphericpressure.

As mentioned, any source of vacuum may be used. For example, the devicemay comprise an internal vacuum source, and/or be connectable to avacuum source is external to the device, such as a vacuum pump or anexternal (line) vacuum source. In some cases, a vacuum may be createdmanually, e.g., by manipulating a syringe pump, a plunger, or the like,or the low pressure may be created mechanically or automatically, e.g.,using a piston pump, a syringe, a bulb, a Venturi tube, manual (mouth)suction, etc., or the like.

In some cases, the device includes an interface that is able to apply avacuum to the skin. The interface may be, for example, a suction cup ora circular bowl that is placed on the surface of the skin, and vacuumapplied to the interface to create a vacuum. In one set of embodiments,the interface is part of a support structure, as discussed herein. Theinterface may be formed from any suitable material, e.g., glass, rubber,polymers such as silicone, polyurethane, nitrile rubber, EPDM rubber,neoprene, or the like. In some cases, the seal between the interface andthe skin may be enhanced (e.g., reducing leakage), for instance, usingvacuum grease, petroleum jelly, a gel, or the like. In some cases, theinterface may be relatively small, for example, having a diameter ofless than about 5 cm, less than about 4 cm, less than about 3 cm, lessthan about 2 cm, less than about 1 cm, less than about 5 mm, less thanabout 4 mm, less than about 3 mm, less than about 2 mm, or less thanabout 1 mm. The interface may be circular, although other shapes arealso possible, for example, square, star-shaped (having 5, 6, 7, 8, 9,10, 11, etc. points), tear-drop, oval, rectangular, or the like. In somecases, non-circular shapes may be used since high-energy points, e.g.,the points or corners of the shape may enhance or accelerate blisterformation.

The interface may also be selected, in some cases, to keep the size ofthe contact region below a certain area, e.g., to minimize pain ordiscomfort to the subject, for aesthetic reasons, or the like. Theinterface may be constructed out of any suitable material, e.g., glass,plastic, or the like.

In one set of embodiments, a device of the present invention may nothave an external power and/or a vacuum source. In some cases, the deviceis “pre-loaded” with a suitable vacuum source; for instance, in oneembodiment, the device may be applied to the skin and activated in somefashion to create and/or access the vacuum source. As one example, adevice of the present invention may be contacted with the skin of asubject, and a vacuum created through a change in shape of a portion ofthe device (e.g., using a shape memory polymer), or the device maycontain one or more sealed, self-contained vacuum chambers, where a sealis punctured in some manner to create a vacuum. For instance, uponpuncturing the seal, a vacuum compartment may be in fluidiccommunication with one or more needles, which can be used to move theskin towards the device, withdraw fluid from the skin and/or beneath theskin, or the like.

As another example, a shape memory polymer may be shaped to be flat at afirst temperature (e.g., room temperature) but curved at a secondtemperature (e.g., body temperature), and when applied to the skin, theshape memory polymer may alter from a flat shape to a curved shape,thereby creating a vacuum. As yet another example, a mechanical devicemay be used to create the vacuum, For example, springs, coils, expandingfoam (e.g., from a compressed state), a shape memory polymer, shapememory metal, or the like may be stored in a compressed or woundreleased upon application to a subject, then released (e.g., unwinding,uncompressing, etc.), to mechanically create the vacuum. Non-limitingexamples of shape-memory polymers and metals include Nitinol,compositions of oligo(epsilon-caprolactone)diol and crystallizableoligo(rho-dioxanone)diol, or compositions ofoligo(epsilon-caprolactone)dimethacrylate and n-butyl acrylate.

In yet another example, a chemical reaction may be used to create avacuum, e.g., a reaction in which a gas is produced, which can beharnessed to provide the mechanical force to create a vacuum. In someembodiments, the device may be used to create a vacuum automatically,once activated, without any external control by a user.

In some cases, the device may be an electrical and/or a mechanicaldevice applicable or affixable to the surface of the skin, e.g., using avacuum, an adhesive, or a combination of adhesives, or other techniquessuch as those described herein. For example, in one set of embodiments,the device may include a support structure that contains an adhesivethat can be used to immobilize the device to the skin. The adhesive maybe permanent or temporary, and may be used to affix the device to thesurface of the skin. The adhesive may be any suitable adhesive, forexample, a pressure sensitive adhesive, a contact adhesive, a permanentadhesive, a cyanoacrylate, glue, gum, hot melts, an epoxy, a hydrogel, ahydrocolloid, or the like. In some cases, the adhesive is chosen to bebiocompatible or hypoallergenic.

In another set of embodiments, the device may be mechanically held tothe skin. For instance, the device may include mechanical elements suchas straps, belts, buckles, strings, ties, elastic bands, or the like.For example, a strap may be worn around the device to hold the device inplace against the skin of the subject. In yet another set ofembodiments, a combination of these and/or other techniques may be used.As one non-limiting example, the device may be affixed to a subject'sarm or leg using adhesive and a strap.

In some aspects, the device may include a support structure forapplication to the skin of the subject. The support structure may beused, as discussed herein, for applying the fluid transporter to thesurface of the skin of the subject, e.g., so that fluid may be deliveredto and/or withdrawn from the skin and/or beneath the skin of thesubject. In some cases, the support structure may immobilize the fluidtransporter such that the fluid transporter cannot move relative to thesupport structure; in other cases, however, the fluid transporter may beable to move relative to the support structure. In one embodiment, as anon-limiting example, the fluid transporter is immobilized relative tothe support structure, and the support structure is positioned withinthe device such that application of the device to the skin causes atleast a portion of the fluid transporter to pierce the skin of thesubject. In some cases, as discussed herein, the support structureincludes a reversibly deformable structure.

For instance, in one set of embodiments, the support structure, or aportion of the support structure, may move from a first position to asecond position. For example, the first position may be one where thesupport structure has immobilized relative thereto a fluid transporterthat does not contact the skin (e.g., the fluid transporter may becontained within a recess), while the second position may be one wherethe fluid transporter does contact the skin, and in some cases, thefluid transporter may pierce the skin. The support structure may bemoved using any suitable technique, e.g., manually, mechanically,electromagnetically, using a servo mechanism, or the like. In one set ofembodiments, for example, the support structure may be moved from afirst position to a second position by pushing a button on the device,which causes the support structure to move (either directly, orindirectly, e.g., through a mechanism linking the button with thesupport structure). Other mechanisms (e.g., dials, levers, sliders,etc., as discussed herein) may be used in conjunction with or instead ofa button. In another set of embodiments, the support structure may bemoved from a first position to a second position automatically, forexample, upon activation by a computing device, upon remote activation,after a period of time has elapsed, or the like. For example, in oneembodiment, a servo connected to the support structure is activatedelectronically, moving the support structure from the first position tothe second position.

In some cases, the support structure may also be moved from the secondposition to the first position. For example, after fluid has beendelivered to and/or withdrawn from the skin and/or beneath the skin,e.g., using a fluid transporter the support structure may be moved,which may move the fluid transporter away from contact with the skin.The support structure may be moved from the second position to the firstposition using any suitable technique, including those described above,and the technique for moving the support structure from the secondposition to the first position may be the same or different as thatmoving the support structure from the first position to the secondposition.

In some cases, the support structure may be able to draw skin towardsthe fluid transporter. For example, in one set of embodiments, thesupport structure may include a vacuum interface, such as is describedherein. The interface may be connected with a vacuum source (externaland/or internal to the device), and when a vacuum is applied, skin maybe drawn towards the support structure, e.g., for contact with a fluidtransporter, such as a needle or a microneedle.

In certain aspects, the device may also contain an activator. Theactivator may be constructed and arranged to cause exposure of the fluidtransporter to the skin upon activation of the activator. For example,the activator may cause a chemical to be released to contact the skin,one or more needles or microneedle to be driven into the skin, a vacuumto be applied to the skin, a jet of fluid to be directed to the skin, orthe like. The activator may be activated by the subject, and/or byanother person (e.g., a health care provider), or the device itself maybe self-activating, e.g., upon application to the skin of a subject. Theactivator may be activated once, or multiple times in some cases.

The device may be activated, for example, by pushing a button, flippinga switch, moving a slider, turning a dial, or the like. The subject,and/or another person, may activate the activator. In some cases, thedevice may be remotely activated. For example, a health care providermay send an electromagnetic signal which is received by the device inorder to activate the device, e.g., a wireless signal, a Bluetoothsignal, an Internet signal, a radio signal, etc.

In some aspects, the device may include channels such as microfluidicchannels, which may be used to deliver and/or withdraw fluids and/orother materials from the skin and/or beneath the skin. In some cases,the microfluidic channels are in fluid communication with a fluidtransporter that is used to deliver to and/or withdraw fluids from theskin and/or beneath the skin. For example, in one set of embodiments,the device may include a hypodermic needle or other needle (e.g., one ormore microneedles) that can be inserted into the skin, and fluid may bedelivered into or through the skin via the needle and/or withdrawn fromthe skin via the needle. The device may also include one or moremicrofluidic channels to contain fluid for delivery to the needle, e.g.,from a source of fluid, and/or to withdraw fluid withdrawn from the skinand/or beneath the skin, e.g., for delivery to an analytical chamberwithin the device, to a reservoir for later analysis, or the like.

In some cases, more than one chamber may be present within the device,and in some cases, some or all of the chambers may be in fluidiccommunication, e.g., via channels such as microfluidic channels. Invarious embodiments, a variety of chambers and/or channels may bepresent within the device, depending on the application. For example,the device may contain chambers for sensing an analyte, chambers forholding reagents, chambers for controlling temperature, chambers forcontrolling pH or other conditions, chambers for creating or bufferingpressure or vacuum, chambers for controlling or dampening fluid flow,mixing chambers, or the like.

Thus, in one set of embodiments, the device may include a microfluidicchannel. As used herein, “microfluidic,” “microscopic,” “microscale,”the “micro-” prefix (for example, as in “microchannel”), and the likegenerally refers to elements or articles having widths or diameters ofless than about 1 mm, and less than about 100 microns (micrometers) insome cases. In some embodiments, larger channels may be used instead of,or in conjunction with, microfluidic channels for any of the embodimentsdiscussed herein. For examples, channels having widths or diameters ofless than about 10 mm, less than about 9 mm, less than about 8 mm, lessthan about 7 mm, less than about 6 mm, less than about 5 mm, less thanabout 4 mm, less than about 3 mm, or less than about 2 mm may be used incertain instances. In some cases, the element or article includes achannel through which a fluid can flow. In all embodiments, specifiedwidths can be a smallest width (i.e. a width as specified where, at thatlocation, the article can have a larger width in a different dimension),or a largest width (i.e. where, at that location, the article has awidth that is no wider than as specified, but can have a length that isgreater). Thus, for instance, the microfluidic channel may have anaverage cross-sectional dimension (e.g., perpendicular to the directionof flow of fluid in the microfluidic channel) of less than about 1 mm,less than about 500 microns, less than about 300 microns, or less thanabout 100 microns. In some cases, the microfluidic channel may have anaverage diameter of less than about 60 microns, less than about 50microns, less than about 40 microns, less than about 30 microns, lessthan about 25 microns, less than about 10 microns, less than about 5microns, less than about 3 microns, or less than about 1 micron.

A “channel,” as used herein, means a feature on or in an article (e.g.,a substrate) that at least partially directs the flow of a fluid. Insome cases, the channel may be formed, at least in part, by a singlecomponent, e.g. an etched substrate or molded unit. The channel can haveany cross-sectional shape, for example, circular, oval, triangular,irregular, square or rectangular (having any aspect ratio), or the like,and can be covered or uncovered (i.e., open to the external environmentsurrounding the channel). In embodiments where the channel is completelycovered, at least one portion of the channel can have a cross-sectionthat is completely enclosed, and/or the entire channel may be completelyenclosed along its entire length with the exception of its inlet andoutlet.

A channel may have an aspect ratio (length to average cross-sectionaldimension), e.g., an aspect ratio of at least about 2:1, more typicallyat least about 3:1, at least about 5:1, at least about 10:1, etc. Asused herein, a “cross-sectional dimension,” in reference to a fluidic ormicrofluidic channel, is measured in a direction generally perpendicularto fluid flow within the channel. A channel generally will includecharacteristics that facilitate control over fluid transport, e.g.,structural characteristics and/or physical or chemical characteristics(hydrophobicity vs. hydrophilicity) and/or other characteristics thatcan exert a force (e.g., a containing force) on a fluid. The fluidwithin the channel may partially or completely fill the channel. In somecases the fluid may be held or confined within the channel or a portionof the channel in some fashion, for example, using surface tension(e.g., such that the fluid is held within the channel within a meniscus,such as a concave or convex meniscus). In an article or substrate, some(or all) of the channels may be of a particular size or less, forexample, having a largest dimension perpendicular to fluid flow of lessthan about 5 mm, less than about 2 mm, less than about 1 mm, less thanabout 500 microns, less than about 200 microns, less than about 100microns, less than about 60 microns, less than about 50 microns, lessthan about 40 microns, less than about 30 microns, less than about 25microns, less than about 10 microns, less than about 3 microns, lessthan about 1 micron, less than about 300 nm, less than about 100 nm,less than about 30 nm, or less than about 10 nm or less in some cases.In one embodiment, the channel is a capillary.

In some cases, the device may contain one or more chambers or reservoirsfor holding fluid. In some cases, the chambers may be in fluidiccommunication with one or more fluid transporters and/or one or moremicrofluidic channels. For instance, the device may contain a chamberfor collecting fluid withdrawn from a subject (e.g., for storage and/orlater analysis), a chamber for containing a fluid for delivery to thesubject (e.g., blood, saline, optionally containing drugs, hormones,vitamins, pharmaceutical agents, or the like), etc.

A variety of materials and methods, according to certain aspects of theinvention, can be used to form the device, e.g., microfluidic channels,chambers, etc. For example, various components of the invention can beformed from solid materials, in which the channels can be formed viamicromachining, film deposition processes such as spin coating andchemical vapor deposition, laser fabrication, photolithographictechniques, etching methods including wet chemical or plasma processes,and the like. See, for example, Scientific American, 248:44-55, 1983(Angell, et al).

In one set of embodiments, various components of the systems and devicesof the invention can be formed of a polymer, for example, an elastomericpolymer such as polydimethylsiloxane (“PDMS”), polytetrafluoroethylene(“PTFE” or Teflon®), or the like. For instance, according to oneembodiment, a microfluidic channel may be implemented by fabricating thefluidic system separately using PDMS or other soft lithographytechniques (details of soft lithography techniques suitable for thisembodiment are discussed in the references titled “Soft Lithography,” byYounan Xia and George M. Whitesides, published in the Annual Review ofMaterial Science, 1998, Vol. 28, pages 153-184, and “Soft Lithography inBiology and Biochemistry,” by George M. Whitesides, Emanuele Ostuni,Shuichi Takayama, Xingyu Jiang and Donald E. Ingber, published in theAnnual Review of Biomedical Engineering, 2001, Vol. 3, pages 335-373;each of these references is incorporated herein by reference).

Other examples of potentially suitable polymers include, but are notlimited to, polyethylene terephthalate (PET), polyacrylate,polymethacrylate, polycarbonate, polystyrene, polyethylene,polypropylene, polyvinylchloride, cyclic olefin copolymer (COC),polytetrafluoroethylene, a fluorinated polymer, a silicone such aspolydimethylsiloxane, polyvinylidene chloride, bis-benzocyclobutene(“BCB”), a polyimide, a polyester, a fluorinated derivative of apolyimide, or the like. Another example is polyethylene terephthalateglycol (“PETG”). In PETG, the ethylene glycol group that is normallypart of the PET chain is partially substituted for cyclohexanedimethanol (e.g., approximately 15-35 mol % of the ethylene groups arereplaced), which may, in some cases, slow down the crystallization ofthe polymer when injection molded to allow better processing.Combinations, copolymers, derivatives, or blends involving polymersincluding those described above are also envisioned. The device may alsobe formed from composite materials, for example, a composite of apolymer and a semiconductor material.

In some embodiments, various components of the invention are fabricatedfrom polymeric and/or flexible and/or elastomeric materials, and can beconveniently formed of a hardenable fluid, facilitating fabrication viamolding (e.g. replica molding, injection molding, cast molding, etc.).The hardenable fluid can be essentially any fluid that can be induced tosolidify, or that spontaneously solidifies, into a solid capable ofcontaining and/or transporting fluids contemplated for use in and withthe fluidic network. In one embodiment, the hardenable fluid comprises apolymeric liquid or a liquid polymeric precursor (i.e. a “prepolymer”).Suitable polymeric liquids can include, for example, thermoplasticpolymers, thermoset polymers, waxes, metals, or mixtures or compositesthereof heated above their melting point. As another example, a suitablepolymeric liquid may include a solution of one or more polymers in asuitable solvent, which solution forms a solid polymeric material uponremoval of the solvent, for example, by evaporation. Such polymericmaterials, which can be solidified from, for example, a melt state or bysolvent evaporation, are well known to those of ordinary skill in theart. A variety of polymeric materials, many of which are elastomeric,are suitable, and are also suitable for forming molds or mold masters,for embodiments where one or both of the mold masters is composed of anelastomeric material. A non-limiting list of examples of such polymersincludes polymers of the general classes of silicone polymers, epoxypolymers, and acrylate polymers. Epoxy polymers are characterized by thepresence of a three-membered cyclic ether group commonly referred to asan epoxy group, 1,2-epoxide, or oxirane. For example, diglycidyl ethersof bisphenol A can be used, in addition to compounds based on aromaticamine, triazine, and cycloaliphatic backbones. Another example includesthe well-known Novolac polymers. Non-limiting examples of siliconeelastomers suitable for use according to the invention include thoseformed from precursors including the chlorosilanes such asmethylchlorosilanes, ethylchlorosilanes, phenylchlorosilanes, etc.

Silicone polymers are used in certain embodiments, for example, thesilicone elastomer polydimethylsiloxane. Non-limiting examples of PDMSpolymers include those sold under the trademark Sylgard by Dow ChemicalCo., Midland, Mich., and particularly Sylgard 182, Sylgard 184, andSylgard 186. Silicone polymers including PDMS have several beneficialproperties simplifying fabrication of the microfluidic structures of theinvention. For instance, such materials are inexpensive, readilyavailable, and can be solidified from a prepolymeric liquid via curingwith heat. For example, PDMSs are typically curable by exposure of theprepolymeric liquid to temperatures of about, for example, about 65° C.to about 75° C. for exposure times of, for example, about an hour. Also,silicone polymers, such as PDMS, can be elastomeric and thus may beuseful for forming very small features with relatively high aspectratios, necessary in certain embodiments of the invention. Flexible(e.g., elastomeric) molds or masters can be advantageous in this regard.

One advantage of forming structures such as microfluidic structures ofthe invention from silicone polymers, such as PDMS, is the ability ofsuch polymers to be oxidized, for example by exposure to anoxygen-containing plasma such as an air plasma, so that the oxidizedstructures contain, at their surface, chemical groups capable ofcross-linking to other oxidized silicone polymer surfaces or to theoxidized surfaces of a variety of other polymeric and non-polymericmaterials. Thus, components can be fabricated and then oxidized andessentially irreversibly sealed to other silicone polymer surfaces, orto the surfaces of other substrates reactive with the oxidized siliconepolymer surfaces, without the need for separate adhesives or othersealing means. In most cases, sealing can be completed simply bycontacting an oxidized silicone surface to another surface without theneed to apply auxiliary pressure to form the seal. That is, thepre-oxidized silicone surface acts as a contact adhesive againstsuitable mating surfaces. Specifically, in addition to beingirreversibly sealable to itself, oxidized silicone such as oxidized PDMScan also be sealed irreversibly to a range of oxidized materials otherthan itself including, for example, glass, silicon, silicon oxide,quartz, silicon nitride, polyethylene, polystyrene, glassy carbon, andepoxy polymers, which have been oxidized in a similar fashion to thePDMS surface (for example, via exposure to an oxygen-containing plasma).Oxidation and sealing methods useful in the context of the presentinvention, as well as overall molding techniques, are described in theart, for example, in an article titled “Rapid Prototyping ofMicrofluidic Systems and Polydimethylsiloxane,” Anal. Chem., 70:474-480,1998 (Duffy et al.), incorporated herein by reference.

Another advantage to forming microfluidic structures of the invention(or interior, fluid-contacting surfaces) from oxidized silicone polymersis that these surfaces can be much more hydrophilic than the surfaces oftypical elastomeric polymers (where a hydrophilic interior surface isdesired). Such hydrophilic channel surfaces can thus be more easilyfilled and wetted with aqueous solutions than can structures comprisedof typical, unoxidized elastomeric polymers or other hydrophobicmaterials.

In one set of embodiments, the device may include a sensor, for exampleembedded within or integrally connected to the device, or positionedremotely but with physical, electrical, and/or optical connection withthe device so as to be able to sense a chamber within or fluid from thedevice. For example, the sensor may be in fluidic communication withfluid withdrawn from a subject, directly, via a microfluidic channel, ananalytical chamber, etc. The sensor may be able to sense an analyte,e.g., one that is suspected of being in a fluid withdrawn from asubject. For example, a sensor may be free of any physical connectionwith the device, but may be positioned so as to detect the results ofinteraction of electromagnetic radiation, such as infrared, ultraviolet,or visible light, which has been directed toward a portion of thedevice, e.g., a chamber within the device. As another example, a sensormay be positioned on or within the device, and may sense activity in achamber by being connected optically to the chamber. Sensingcommunication can also be provided where the chamber is in communicationwith a sensor fluidly, optically or visually, thermally, pneumatically,electronically, or the like, so as to be able to sense a condition ofthe chamber. As one example, the sensor may be positioned downstream ofa chamber, within a channel such a microfluidic channel, on an externalapparatus, or the like. Accordingly, the device, in certain embodiments,may contain a portion able to determine a fluid removed from the skin.For example, a portion of the device may contain a sensor(s), orreagents able to interact with an analyte contained or suspected to bepresent within the withdrawn fluid from the skin of the subject, forexample, a marker for a disease state

The sensor may be or include, for example, a pH sensor, an opticalsensor, an oxygen sensor, a sensor able to detect the concentration of asubstance, or the like. Non-limiting examples of sensors useful in theinvention include dye-based detection systems, affinity-based detectionsystems, microfabricated gravimetric analyzers, CCD cameras, opticaldetectors, optical microscopy systems, electrical systems, thermocouplesand thermistors, pressure sensors, ion-sensitive field-effecttransistors and arrays of them, etc. Those of ordinary skill in the artwill be able to identify other suitable sensors for use in theinvention. The sensor can include a colorimetric detection system insome cases, which may be external to the device, or microfabricated intothe device in certain cases. As an example of a colorimetric detectionsystem, if a dye or a fluorescent entity is used (e.g. in a particle),the colorimetric detection system may be able to detect a change orshift in the frequency and/or intensity of the dye or fluorescententity.

Examples of sensors include, but are not limited to, pH sensors, opticalsensors, ion sensors, colorimetric sensors, a sensor able to detect theconcentration of a substance, or the like, e.g., as discussed herein.For instance, in one set of embodiments, the device may include anion-selective electrode. The ion selective electrode may be able todetermine a specific ion and/or ions such as K⁺, H⁺, Na⁺, Ag⁺, Pb²⁺,Cd²⁺, or the like. Various ion selective electrodes can be obtainedcommercially. As a non-limiting example, a potassium-selective electrodemay include an ion exchange resin membrane, using valinomycin, apotassium channel, as the ion carrier in the membrane to providepotassium specificity.

Examples of analytes that the sensor may be used to determine include,but are not limited to, pH or metal ions, proteins, nucleic acids (e.g.DNA, RNA, etc.), drugs, sugars (e.g., glucose), hormones (e.g.,estradiol, estrone, progesterone, progestin, testosterone,androstenedione, etc.), carbohydrates, or other analytes of interest.Other conditions that can be determined can include pH changes, whichmay indicate disease, yeast infection, periodontal disease at a mucosalsurface, oxygen or carbon monoxide levels which indicate lungdysfunction, and drug levels, both legal prescription levels of drugssuch as coumadin, other drugs such as nicotine, or illegal drugs such ascocaine. For example, an external reward may be offered if no (orreduced levels of) illegal drugs are determined in the subject. Asanother example, the substance may be a banned performance-enhancingdrug, and an external reward may be offered if the drug is notdetermined within the subject (e.g., an athlete). Further examples ofanalytes include those indicative of disease, such as cancer specificmarkers such as CEA and PSA, viral and bacterial antigens, andautoimmune indicators such as antibodies to double stranded DNA,indicative of Lupus. Still other conditions include exposure to elevatedcarbon monoxide, which could be from an external source or due to sleepapnea, too much heat (important in the case of babies whose internaltemperature controls are not fully self-regulating) or from fever. Stillother potentially suitable analytes include various pathogens such asbacteria or viruses, and/or markers produced by such pathogens.

As additional non-limiting examples, the sensor may contain an antibodyable to interact with a marker for a disease state, an enzyme such asglucose oxidase or glucose 1-dehydrogenase able to detect glucose, orthe like. The analyte may be determined quantitatively or qualitatively,and/or the presence or absence of the analyte within the withdrawn fluidmay be determined in some cases. Those of ordinary skill in the art willbe aware of many suitable commercially-available sensors, and thespecific sensor used may depend on the particular analyte being sensed.For instance, various non-limiting examples of sensor techniques includepressure or temperature measurements, spectroscopy such as infrared,absorption, fluorescence, UV/visible, FTIR (“Fourier Transform InfraredSpectroscopy”), or Raman; piezoelectric measurements; immunoassays;electrical measurements, electrochemical measurements (e.g.,ion-specific electrodes); magnetic measurements, optical measurementssuch as optical density measurements; circular dichroism; lightscattering measurements such as quasielectric light scattering;polarimetry; refractometry; chemical indicators such as dyes; orturbidity measurements, including nephelometry.

Still other potentially suitable analytes include various pathogens suchas bacteria or viruses, and/or markers produced by such pathogens. Thus,in certain embodiments of the invention, as discussed below, one or moreanalytes may be determined in some fashion, which may be useful indetermining a past, present and/or future condition of the subject.

In one set of embodiments, the sensor may be a test strip, for example,test strips that can be obtained commercially. Examples of test stripsinclude, but are not limited to, glucose test strips, urine test strips,pregnancy test strips, or the like. A test strip will typically includea band, piece, or strip of paper or other material and contain one ormore regions able to determine an analyte, e.g., via binding of theanalyte to a diagnostic agent or a reaction entity able to interact withand/or associate with the analyte. For example, the test strip mayinclude various enzymes or antibodies, glucose oxidase and/orferricyanide, or the like. The test strip may be able to determine, forexample, glucose, cholesterol, creatinine, ketones, blood, protein,nitrite, pH, urobilinogen, bilirubin, leucocytes, luteinizing hormone,etc., depending on the type of test strip. The test strip may be used inany number of different ways. In some cases, a test strip may beobtained commercially and inserted into the device, e.g., before orafter withdrawing blood, interstitial fluid, or other fluids from asubject. At least a portion of the blood or other fluid may be exposedto the test strip to determine an analyte, e.g., in embodiments wherethe device uses the test strip as a sensor so that the device itselfdetermines the analyte. In some cases, the device may be sold with atest strip pre-loaded, or a user may need to insert a test strip in adevice (and optionally, withdraw and replace the test strip betweenuses). In certain cases, the test strip may form an integral part of thedevice that is not removable by a user. In some embodiments, afterexposure to the blood or other fluid withdrawn from the subject, thetest strip may be removed from the device and determined externally,e.g., using other apparatuses able to determine the test strip, forexample, commercially-available test strip readers.

In one embodiment, an analyte may be determined as an “on/off” or“normal/abnormal” situation. Detection of the analyte, for example, maybe indicative that insulin is needed; a trip to the doctor to checkcholesterol; ovulation is occurring; kidney dialysis is needed; druglevels are present (e.g., especially in the case of illegal drugs) ortoo high/too low (e.g., important in care of geriatrics in particular innursing homes). As another embodiment, however, an analyte may bedetermined quantitatively.

As described herein, any of a variety of signaling or display methods,associated with analyses, can be provided including signaling visually,by smell, sound, feel, taste, or the like, in one set of embodiments.Signal structures or generators include, but are not limited to,displays (visual, LED, light, etc.), speakers, chemical-releasingchambers (e.g., containing a volatile chemical), mechanical devices,heaters, coolers, or the like. In some cases, the signal structure orgenerator may be integral with the device (e.g., integrally connectedwith a support structure for application to the skin of the subject,e.g., containing a fluid transporter such as one or more needles ormicroneedles), or the signal structure may not be integrally connectedwith the support structure. As used herein, a “signal structure” or a“signal generator” is any apparatus able to generate a signal that isrelated to a condition of a medium. For example, the medium may be abodily fluid, such as blood or interstitial fluid.

In some embodiments, signaling methods such as these may be used toindicate the presence and/or concentration of an analyte determined bythe sensor, e.g., to the subject, and/or to another entity, such asthose described below. Where a visual signal is provided, it can beprovided in the form of change in opaqueness, a change in intensity ofcolor and/or opaqueness, or can be in the form of a message (e.g.,numerical signal, or the like), an icon (e.g., signaling by shape orotherwise a particular medical condition), a brand, logo, or the like.For instance, in one embodiment, the device may include a display. Awritten message such as “take next dose,” or “glucose level is high” ora numerical value might be provided, or a message such as “toxin ispresent.” These messages, icons, logos, or the like can be provided asan electronic read-out by a component of a device and/or can bedisplayed as in inherent arrangement of one or more components of thedevice.

In some embodiments, a device is provided where the device determines aphysical condition of a subject and produces a signal related to thecondition that can be readily understood by the subject (e.g., byprovision of a visual “OK” signal as described above) or can be designedso as not to be readily understandable by a subject. Where not readilyunderstandable, the signal can take a variety of forms. In one form, thesignal might be a series of letters or numbers that mean nothing to thesubject (e.g., A1278CDQ) which would have meaning to a medicalprofessional or the like (and/or be decodable by the same, e.g., withreference to a suitable decoder) and can be associated with a particularphysiological condition. Alternatively, a signal in the form of bar codecan be provided by a device such that, under a particular condition orset of conditions the bar code appears and/or disappears, or changes,and can be read by a bar code reader to communicate information aboutthe subject or analyte. In another embodiment, the device can bedesigned such that an ultraviolet signal is produced, or a signal thatcan be read only under ultraviolet light (e.g., a simple spot or patch,or any other signal such as a series of number, letters, bar code,message, or the like that can be readily understandable or not readilyunderstandable by a subject) can be provided. The signal may beinvisible to the human eye but, upon application UV light or otherexcitation energy, may be readable. The signal can be easily readable orunderstandable by a user via visual observation, or with other sensoryactivity such smell, feel, etc. In another set of embodiments equipmentas described above may be needed to determine a signal provided by thedevice, such as equipment in a clinical setting, etc. In some cases, thedevice is able to transmit a signal indicative of the analyte to areceiver, e.g., as a wireless signal, a radio signal, etc.

In some embodiments, quantitative and/or qualitative analyses can beprovided by a device. That is, the device in some cases may provideanalyses that allow “yes/no” tests or the like, or tests that provideinformation on the quantity, concentration, or level of a particularanalyte or analytes. Display configurations can be provided by theinvention that reflect the amount of a particular analyte present in asubject at a particular point in time, or any other variable (presenceof analysis over time, type of analyte, etc.) display configurations cantake a variety of forms. In one example, a dial can be provided, similarto that of a speedometer with a series of level indications (e.g.,numbers around the dial) and a “needle” or other device that indicates aparticular level. In other configurations, a particular area of thedevice (e.g., on a display) can exist that is filled in to a greater orlesser extent depending upon the presence and/or quantity of aparticular analyte present, e.g., in the form of a bar graph. In anotherarrangement a “color wheel” can be provided where the amount of aparticular analyte present can control which colors of the wheel arevisible. Or, different analytes can cause different colors of a wheel ordifferent bars of a graph to become visible or invisible in a multipleanalyte analysis. Multiple-analyte quantitative analyses can bereflected in multiple color wheels, a single color wheel with differentcolors per analyte where the intensity of each color reflects the amountof the analyte, or, for example, a plurality of bar graphs where eachbar graph is reflective of a particular analyte and the level of the bar(and/or degree to which an area is filled in with visible color or othervisible feature) is reflective of the amount of the analyte. As with allembodiments here, whatever signal is displayed can be understandable ornot understandable to any number of participants. For example, it can beunderstandable to a subject or not understandable to a subject. Wherenot understandable it might need to be decoded, read electronically, orthe like. Where read electronically, for example, a device may provide asignal that is not understandable to a subject or not even visible orotherwise able to be sensed by a subject, and a reader can be providedadjacent or approximate the device that can provide a visible signalthat is understandable or not understandable to the subject, or cantransmit a signal to another entity for analysis.

The display may also be used to display other information, in additionor instead of the above. For example, the device may include one or moredisplays that indicate when the device has been used or has beenexpired, that indicate that sampling of fluid from a subject is ongoingand/or complete, or that a problem has occurred with sampling (e.g.,clogging or insufficient fluid collected), that indicate that analysisof an analyte within the collected sample is ongoing and/or complete,that an adequate amount of a fluid has been delivered to the subject (orthat an inadequate amount has been delivered, and/or that fluid deliveryis ongoing), that the device can be removed from the skin of the subject(e.g., upon completion of delivery and/or withdrawal of a fluid, and/orupon suitable analysis, transmission, etc.), or the like.

In connection with any signals associated with any analyses describedherein, another, potentially related signal or other display (or smell,taste, or the like) can be provided which can assist in interpretingand/or evaluating the signal. In one arrangement, a calibration orcontrol is provided proximate (or otherwise easily comparable with) asignal, e.g., a visual calibration/control or comparator next to orclose to a visual signal provided by a device and/or implanted agents,particles, or the like.

A visual control or reference can be used with another sensory signal,such as that of smell, taste, temperature, itch, etc. Areference/control and/or experimental confirmation component can beprovided, to be used in connection with an in-skin test or vice versa.References/indicators can also be used to indicate the state of life ofa device, changing color or intensity and/or changing in anothersignaling aspect as the device changes relative to its useful life, sothat a user can determine when the device should no longer be reliedupon and/or removed. For certain devices, an indicator or control can beaffected by adding analyte to the control (e.g., from a source outsideof the source to be determine) to confirm operability of the deviceand/or to provide a reference against which to measure a signal of thedevice. For example, a device can include a button to be tapped by auser which will allow an analyte from a reservoir to transfer to anindicator region to provide a signal, to demonstrate operability of thedevice and/or provide a comparator for analysis.

Many of the embodiments described herein involve a quantitative analysisand related signal, i.e., the ability to determine the relative amountor concentration of an analyte in a medium. This can be accomplished ina variety of ways. For example, where an agent (e.g. a binding partnerattached to a nanoparticle) is used to capture and analyze an analyte,the agent can be provided in a gradient in concentration across asensing region of the device. Or a sensing region can include a membraneor other apparatus through which analyte is required to flow or passprior to capture and identification, and the pathway for analyte travelcan vary as a function of position of display region. For example, amembrane can be provided across a sensing region, through which analytemust pass prior to interacting with a layer of binding and/or signalingagent, and the membrane may vary in thickness laterally in a directionrelated to “bar graph” readout. Where a small amount of analyte ispresent, it may pass through the thinner portion but not the thickerportion of the membrane, but where a larger amount is present, it maypass across a thicker portion. The boundary (where one exists) between aregion through which analyte passes, and one through which it does notcompletely pass, can define the “line” of the bar graph. Other ways ofachieving the same or a similar result can include varying theconcentration of a scavenger or transporter of the analyte, or anintermediate reactive species (between analyte and signaling event),across a membrane or other article, gradient in porosity or selectivityof the membrane, ability to absorb or transport sample fluid, or thelike. These principles, in combination with other disclosure herein, canbe used to facilitate any or all of the quantitative analyses describedherein.

In one aspect, a subject having a condition such as a physiologicalcondition to be analyzed (or other user, such as medical personnel)reads and/or otherwise determines a signal from a device. For example,the device may transmit a signal indicative of a condition of thesubject and/or the device. Alternatively, or in addition, a signalproduced by a device can be acquired in the form of a representation(e.g. a digitized signal, or the like) and transmitted to another entityfor analysis and/or action. For example, a signal can be produced by adevice, e.g., based on a sensor reading of an analyte, based on fluiddelivered and/or withdrawn from the skin and/or beneath the skin, basedon a condition of the device, or the like. The signal may represent anysuitable data or image. For example, the signal may represent thepresence and/or concentration of an analyte in fluid withdrawn from asubject, the amount of fluid withdrawn from a subject and/or deliveredto the subject, the number of times the device has been used, thebattery life of the device, the amount of vacuum left in the device, thecleanliness or sterility of the device, the identity of the device(e.g., where multiple devices are given unique identification numbers,to prevent counterfeiting, accidental exchange of equipment to incorrectusers, etc.), or the like. For instance, in one set of embodiments, animage of the signal (e.g., a visual image or photograph) can be obtainedand transmitted to a different entity (for example, a user can take acell phone picture of a signal generated by the device and send it, viacell phone, the other entity).

The other entity that the signal is transmitted to can be a human (e.g.,a clinician) or a machine. In some cases, the other entity may be ableto analyze the signal and take appropriate action. In one arrangement,the other entity is a machine or processor that analyzes the signal andoptionally sends a signal back to the device to give direction as toactivity (e.g., a cell phone can be used to transmit an image of asignal to a processor which, under one set of conditions, transmits asignal back to the same cell phone giving direction to the user, ortakes other action). Other actions can include automatic stimulation ofthe device or a related device to dispense a medicament orpharmaceutical, or the like. The signal to direct dispensing of apharmaceutical can take place via the same used to transmit the signalto the entity (e.g., cell phone) or a different vehicle or pathway.Telephone transmission lines, wireless networks, Internet communication,and the like can also facilitate communication of this type.

As one specific example, a device may be a glucose monitor. As signalmay be generated by the device and an image of the signal captured by acell phone camera and then transmitted via cell phone to a clinician.The clinician may then determine that the glucose (or e.g., insulin)level is appropriate or inappropriate and send a message indicating thisback to the subject via cell phone.

Information regarding the analysis can also be transmitted to the sameor a different entity, or a different location simply by removing thedevice or a portion of the device from the skin of the subject andtransferring it to a different location. For example, a device can beused in connection with a subject to analyze presence and/or amount of aparticular analyte. At some point after the onset of use, the device, ora portion of the device carrying a signal or signals indicative of theanalysis or analyses, can be removed and, e.g., attached to a recordassociated with the subject. As a specific example, a patch or otherdevice can be worn by a subject to determine presence and/or amount ofone or more analytes qualitatively, quantitatively, and/or over time.The subject can visit a clinician who can remove the patch or a portionof the patch and attach it to a medical record associated with thesubject.

According to various aspects, the device may be used one, or multipletimes, depending on the application. For instance, obtaining samples forsensing, according to certain embodiments of the invention, can be donesuch that sensing can be carried out continuously, discretely, or acombination of these. For example, where a bodily fluid such as blood orinterstitial fluid is accessed for determination of an analyte, fluidcan be accessed discretely (i.e., as a single dose, once or multipletimes), or continuously by creating a continuous flow of fluid which canbe analyzed once or any number of times. Additionally, testing can becarried out once, at a single point in time, or at multiple points intime, and/or from multiple samples (e.g., at multiple locations relativeto the subject).

Alternatively or in addition, testing can be carried out continuouslyover any number of points in time involving one or any number oflocations relative to the subject or other multiple samples. As anexample, one bolus or isolated sample, of fluid such as blood orinterstitial fluid can be obtained. From that fluid a test can becarried out to determine whether a particular analyte or other agentexists in the fluid. Alternatively, two or more tests can be carried outinvolving that quantity of fluid to determine the presence and/orquantity of two or more analytes, and any number of such tests can becarried out. Tests involving that quantity of fluid can be carried outsimultaneously or over a period of time. For example, a test for aparticular analyte can be carried out at various points in time todetermine whether the result changes over time, or different analytescan be determined at different points in time. As another example, apool of fluid can be formed between layers of skin via, e.g., a suctionblister, and either within the suction blister or from fluid drawn fromthe suction blister and placed elsewhere, any of the above and otheranalysis can be carried out at one or more points in time. In somecases, a suction blister is formed in such a way that the interstitialfluid within the blister changes over time (e.g., where an equilibriumexists between interstitial fluid within the subject and interstitialfluid in the suction blister itself, i.e., the fluid within the blisteris ever changing to reflect the content of the interstitial fluid of thesubject in the region of the blister over time). Testing of fluid withinor from the suction blister at various points in time can provide usefulinformation.

In another example, one or more needles or microneedles, or otherdevice(s) can be used to access a fluid of a subject such as blood orinterstitial fluid (with or without use of a suction blister). Fluid canbe drawn to a point of analysis and analyzed in any manner describedherein. For example, an analysis can be carried out once, to determinethe presence and/or quantity of a single analyte, or a number of testscan be carried out. From a single sample of fluid, a particular test ornumber of tests can be carried out essentially simultaneously, oranalyses can be carried out over time. Moreover, fluid can be drawncontinuously from the skin and/or beneath the skin of the subject andone or more tests can be carried out of any number of points in time. Avariety of reasons for carrying out one or more tests over the course oftime exists, as would be understood by those of ordinary skill in theart. One such reason is to determine whether the quantity or anothercharacteristic of an analyte is constant in a subject, or changes overtime. A variety of specific techniques for continuous and/or discretetesting will be described herein.

In some aspects, one or materials, such as particles, are delivered toor through the skin. Examples of suitable materials include, but are notlimited to, particles such as microparticles or nanoparticles, achemical, a drug or a pharmaceutical substance, a diagnostic agent, acarrier, or the like. The particles may be, for example, nanoparticlesor microparticles, and in some cases, the particles may be anisotropicparticles. In some cases, a plurality of particles may be used, and insome cases, some, or substantially all, of the particles may be thesame. For example, at least about 10%, at least about 30%, at leastabout 40%, at least about 50%, at least about 60%, at least about 70%,at least about 80%, at least about 90%, at least about 95%, or at leastabout 99% of the particles may have the same shape, and/or may have thesame composition.

The particles may be used for a variety of purposes. For instance, theparticles may contain a diagnostic agent or a reaction entity able tointeract with and/or associate with an analyte, or another reactionentity, or other particles. Such particles may be useful, for example,to determine one or more analytes, such as a marker of a disease state,as discussed below. As another example, the particles may contain a drugor a pharmaceutical substance, positioned on the surface and/orinternally of the particles, which may be released by the particles anddelivered to the subject. Specific examples of these and otherembodiments are discussed in detail below.

In some cases, materials such as particles may become embedded withinthe skin, for example, due to physical properties of the materials(e.g., size, hydrophobicity, etc.). Thus, in some cases, a depot ofmaterial may be formed within the skin, and the depot may be temporaryor permanent. For instance, materials within the depot may eventuallydegrade (e.g., if the material biodegradable), enter the bloodstream, orbe sloughed off to the environment, e.g., as the cells of the dermisdifferentiate to form new epidermis and accordingly push the materialtowards the surface of the skin. Thus, the depot of material may bepresent within the subject on a temporary basis (e.g., on a time scaleof days or weeks), in certain instances.

As mentioned, certain aspects of the present invention are generallydirected to particles such as anisotropic particles or colloids, whichcan be used in a wide variety of applications. For instance, theparticles may be present within the skin, or externally of the skin,e.g., in a device on the surface of the skin. The particles may includemicroparticles and/or nanoparticles. As discussed above, a“microparticle” is a particle having an average diameter on the order ofmicrometers (i.e., between about 1 micrometer and about 1 mm), while a“nanoparticle” is a particle having an average diameter on the order ofnanometers (i.e., between about 1 nm and about 1 micrometer. Theparticles may be spherical or non-spherical, in some cases. For example,the particles may be oblong or elongated, or have other shapes such asthose disclosed in U.S. patent application Ser. No. 11/851,974, filedSep. 7, 2007, titled “Engineering Shape of Polymeric Micro- andNanoparticles,” by S. Mitragotri, et al.; International PatentApplication No. PCT/US2007/077889, filed Sep. 7, 2007, titled“Engineering Shape of Polymeric Micro- and Nanoparticles,” by S.Mitragotri, et al., published as WO 2008/031035 on Mar. 13, 2008; U.S.patent application Ser. No. 11/272,194, filed Nov. 10, 2005, titled“Multi-phasic Nanoparticles,” by J. Lahann, et al., published as U.S.Patent Application Publication No. 2006/0201390 on Sep. 14, 2006; orU.S. patent application Ser. No. 11/763,842, filed Jun. 15, 2007, titled“Multi-Phasic Bioadhesive Nano-Objects as Biofunctional Elements in DrugDelivery Systems,” by J. Lahann, published as U.S. Patent ApplicationPublication No. 2007/0237800 on Oct. 11, 2007, each of which isincorporated herein by reference. Other examples of particles can beseen in U.S. patent application Ser. No. 11/272,194, filed Nov. 10,2005, titled “Multi-phasic Nanoparticles,” by J. Lahann, et al.,published as U.S. Patent Application Publication No. 2006/0201390 onSep. 14, 2006; U.S. patent application Ser. No. 11/763,842, filed Jun.15, 2007, titled “Multi-Phasic Bioadhesive Nan-Objects as BiofunctionalElements in Drug Delivery Systems,” by J. Lahann, published as U.S.Patent Application Publication No. 2007/0237800 on Oct. 11, 2007; orU.S. Provisional Patent Application Ser. No. 61/058,796, filed Jun. 4,2008, titled “Compositions and Methods for Diagnostics, Therapies, andOther Applications,” by D. Levinson, each of which is incorporatedherein by reference.

The particles may be formed of any suitable material, depending on theapplication. For example, the particles may comprise a glass, and/or apolymer such as polyethylene, polystyrene, silicone, polyfluoroethylene,polyacrylic acid, a polyamide (e.g., nylon), polycarbonate, polysulfone,polyurethane, polybutadiene, polybutylene, polyethersulfone,polyetherimide, polyphenylene oxide, polymethylpentene,polyvinylchloride, polyvinylidene chloride, polyphthalamide,polyphenylene sulfide, polyester, polyetheretherketone, polyimide,polymethylmethacylate and/or polypropylene. In some cases, the particlesmay comprise a ceramic such as tricalcium phosphate, hydroxyapatite,fluorapatite, aluminum oxide, or zirconium oxide. In some cases (forexample, in certain biological applications), the particles may beformed from biocompatible and/or biodegradable polymers such aspolylactic and/or polyglycolic acids, polyanhydride, polycaprolactone,polyethylene oxide, polyacrylamide, polyacrylic acid, polybutyleneterephthalate, starch, cellulose, chitosan, and/or combinations ofthese. In one set of embodiments, the particles may comprise a hydrogel,such as agarose, collagen, or fibrin. The particles may include amagnetically susceptible material in some cases, e.g., a materialdisplaying paramagnetism or ferromagnetism. For instance, the particlesmay include iron, iron oxide, magnetite, hematite, or some othercompound containing iron, or the like. In another embodiment, theparticles can include a conductive material (e.g., a metal such astitanium, copper, platinum, silver, gold, tantalum, palladium, rhodium,etc.), or a semiconductive material (e.g., silicon, germanium, CdSe,CdS, etc.). Other particles potentially useful in the practice of theinvention include ZnS, ZnO, TiO₂, AgI, AgBr, HgI₂, PbS, PbSe, ZnTe,CdTe, In₂S₃, In₂Se₃, Cd₃P₂, Cd₃As₂, InAs, or GaAs. The particles mayinclude other species as well, such as cells, biochemical species suchas nucleic acids (e.g., RNA, DNA, PNA, etc.), proteins, peptides,enzymes, nanoparticles, quantum dots, fragrances, indicators, dyes,fluorescent species, chemicals, small molecules (e.g., having amolecular weight of less than about 1 kDa), or the like.

The particles may also have any shape or size. For instance, theparticles may have an average diameter of less than about 5 mm or 2 mm,or less than about 1 mm, or less than about 500 microns, less than about200 microns, less than about 100 microns, less than about 60 microns,less than about 50 microns, less than about 40 microns, less than about30 microns, less than about 25 microns, less than about 10 microns, lessthan about 3 microns, less than about 1 micron, less than about 300 nm,less than about 100 nm, less than about 30 nm, or less than about 10 nm.As discussed, the particles may be spherical or non-spherical. Theaverage diameter of a non-spherical particle is the diameter of aperfect sphere having the same volume as the non-spherical particle. Ifthe particle is non-spherical, the particle may have a shape of, forinstance, an ellipsoid, a cube, a fiber, a tube, a rod, or an irregularshape. In some cases, the particles may be hollow or porous. Othershapes are also possible, for instance, core/shell structures (e.g.,having different compositions), rectangular disks, high aspect ratiorectangular disks, high aspect ratio rods, worms, oblate ellipses,prolate ellipses, elliptical disks, UFOs, circular disks, barrels,bullets, pills, pulleys, biconvex lenses, ribbons, ravioli, flat pills,bicones, diamond disks, emarginate disks, elongated hexagonal disks,tacos, wrinkled prolate ellipsoids, wrinkled oblate ellipsoids, porousellipsoid disks, and the like. See, e.g., International PatentApplication No. PCT/US2007/077889, filed Sep. 7, 2007, titled“Engineering Shape of Polymeric Micro- and Nanoparticles,” by S.Mitragotri, et al., published as WO 2008/031035 on Mar. 13, 2008,incorporated herein by reference.

In one aspect of the invention, a particle may include one or morereaction entities present on the surface (or at least a portion of thesurface) of the particle. The reaction entity may be any entity able tointeract with and/or associate with an analyte, or another reactionentity. For instance, the reaction entity may be a binding partner ableto bind an analyte. For example, the reaction entity may be a moleculethat can undergo binding with a particular analyte. The reactionentities may be used, for example, to determine pH or metal ions,proteins, nucleic acids (e.g. DNA, RNA, etc.), drugs, sugars (e.g.,glucose), hormones (e.g., estradiol, estrone, progesterone, progestin,testosterone, androstenedione, etc.), carbohydrates, or other analytesof interest.

The term “binding partner” refers to a molecule that can undergo bindingwith a particular molecule, e.g., an analyte. For example, the bindingmay be highly specific and/or non-covalent. Binding partners which formhighly specific, non-covalent, physiochemical interactions with oneanother are defined herein as “complementary.” Biological bindingpartners are examples. For example, Protein A is a binding partner ofthe biological molecule IgG, and vice versa. Other non-limiting examplesinclude nucleic acid-nucleic acid binding, nucleic acid-protein binding,protein-protein binding, enzyme-substrate binding, receptor-ligandbinding, receptor-hormone binding, antibody-antigen binding, etc.Binding partners include specific, semi-specific, and non-specificbinding partners as known to those of ordinary skill in the art. Forexample, Protein A is usually regarded as a “non-specific” orsemi-specific binder. As another example, the particles may contain anenzyme such as glucose oxidase or glucose 1-dehydrogenase, or a lectinsuch as concanavalin A that is able to bind to glucose.

As additional examples, binding partners may include antibody/antigenpairs, ligand/receptor pairs, enzyme/substrate pairs and complementarynucleic acids or aptamers. Examples of suitable epitopes which may beused for antibody/antigen binding pairs include, but are not limited to,HA, FLAG, c-Myc, glutathione-S-transferase, His₆, GFP, DIG, biotin andavidin. Antibodies may be monoclonal or polyclonal. Suitable antibodiesfor use as binding partners include antigen-binding fragments, includingseparate heavy chains, light chains Fab, Fab′, F(ab′)₂, Fabc, and Fv.Antibodies also include bispecific or bifunctional antibodies. Exemplarybinding partners include biotin/avidin, biotin/streptavidin,biotin/neutravidin and glutathione-S-transferase/glutathione.

The term “binding” generally refers to the interaction between acorresponding pair of molecules or surfaces that exhibit mutual affinityor binding capacity, typically due to specific or non-specific bindingor interaction, including, but not limited to, biochemical,physiological, and/or chemical interactions. The binding may be betweenbiological molecules, including proteins, nucleic acids, glycoproteins,carbohydrates, hormones, or the like. Specific non-limiting examplesinclude antibody/antigen, antibody/hapten, enzyme/substrate,enzyme/inhibitor, enzyme/cofactor, binding protein/substrate, carrierprotein/substrate, lectin/carbohydrate, receptor/hormone,receptor/effector, complementary strands of nucleic acid,protein/nucleic acid repressor/inducer, ligand/cell surface receptor,virus/ligand, virus/cell surface receptor, etc. As another example, thebinding agent may be a chelating agent (e.g., ethylenediaminetetraaceticacid) or an ion selective polymer (e.g., a block copolymer such aspoly(carbonate-b-dimethylsiloxane), a crown ether, or the like). Asanother example, the binding partners may be biotin and streptavidin, orthe binding partners may be various antibodies raised against a protein.

The term “specifically binds,” when referring to a binding partner(e.g., protein, nucleic acid, antibody, etc.), refers to a reaction thatis determinative of the presence and/or identity of one or other memberof the binding pair in a mixture of heterogeneous molecules (e.g.,proteins and other biologics). Thus, for example, in the case of areceptor/ligand binding pair, the ligand would specifically and/orpreferentially select its receptor from a complex mixture of molecules,or vice versa. An enzyme would specifically bind to its substrate, anucleic acid would specifically bind to its complement, an antibodywould specifically bind to its antigen, etc. The binding may be by oneor more of a variety of mechanisms including, but not limited to ionicinteractions or electrostatic interactions, covalent interactions,hydrophobic interactions, van der Waals interactions, etc.

Thus, the invention provides, in certain embodiments, particles that areable to bind to an analyte, e.g., via a binding partner to the analyte,and such particles can be used to determine the analyte. Suchdetermination may occur within the skin, and/or externally of thesubject, e.g., within a device on the surface of the skin, depending onthe embodiment. “Determine,” in this context, generally refers to theanalysis of a species, for example, quantitatively or qualitatively,and/or the detection of the presence or absence of the species.“Determining” may also refer to the analysis of an interaction betweentwo or more species, for example, quantitatively or qualitatively,and/or by detecting the presence or absence of the interaction, e.g.determination of the binding between two species. “Determining” alsomeans detecting or quantifying interaction between species. As anexample, an analyte may cause a determinable change in a property of theparticles, e.g., a change in a chemical property of the particles, achange in the appearance and/or optical properties of the particles, achange in the temperature of the particles, a change in an electricalproperty of the particles, etc. In some cases, the change may be onethat is determinable by a human, unaided by any equipment that may bedirectly applied to the human. For instance, the determinable change maybe a change in appearance (e.g., color), a change in temperature, theproduction of an odor, etc., which can be determined by a human withoutthe use of any equipment (e.g., using the eyes). Non-limiting examplesinclude temperature changes, chemical reactions or other interactions(e.g., with capsaicin) that can be sensed, or the like. Examples ofcapsaicin and capsaicin-like molecules include, but are not limited to,dihydrocapsaicin, nordihydrocapsaicin, homodihydrocapsaicin,homocapsaicin, or nonivamide. Without wishing to be bound by any theory,it is believed that interactions with capsaicin and capsaicin-likemolecules can be sensed by a subject, since such molecules may interactwith certain nerve endings, which produces a sensation of burning.

In some cases, the particles may contain a diagnostic agent able todetermine an analyte. An example of an analyte within a subject isglucose (e.g., for diabetics); other potentially suitable analytesinclude ions such as sodium, potassium, chloride, calcium, magnesium,and/or bicarbonate (e.g., to determine dehydration); gases such ascarbon dioxide or oxygen; pH; metabolites such as urea, blood ureanitrogen or creatinine; hormones such as estradiol, estrone,progesterone, progestin, testosterone, androstenedione, etc. (e.g., todetermine pregnancy, illicit drug use, or the like); or cholesterol.Still other potentially suitable analytes include various pathogens suchas bacteria or viruses, and/or markers produced by such pathogens. Forexample, a particle may include an antibody directed at a markerproduced by a bacteria. In addition, more than one analyte may bedetermined in a subject, e.g., through the use of different particletypes and/or through the use of particles able to determine more thanone analyte, such as those discussed above. For instance, a first set ofparticles may determine a first analyte and a second set of particlesmay determine a second analyte. In some cases, such particles may beused to determine a physical condition of a subject. For instance, theparticles may exhibit a first color indicating a healthy state and asecond color indicating a disease state. In some cases, the appearanceof the particles may be used to determine a degree of health. Forinstance, the particles may exhibit a first color indicating a healthystate, a second color indicating a warning state, and a third colorindicating a dangerous state, or the particles may exhibit a range ofcolors indicating a degree of health of the subject.

Binding partners to these and/or other species are well-known in theart. Non-limiting examples include pH-sensitive entities such as phenolred, bromothymol blue, chlorophenol red, fluorescein, HPTS,5(6)-carboxy-2′,7′-dimethoxyfluorescein SNARF, and phenothalein;entities sensitive to calcium such as Fura-2 and Indo-1; entitiessensitive to chloride such as 6-methoxy-N-(3-sulfopropyl)-quinolinim andlucigenin; entities sensitive to nitric oxide such as4-amino-5-methylamino-2′,7′-difluorofluorescein; entities sensitive todissolved oxygen such as tris(4,4′-diphenyl-2,2′-bipyridine) ruthenium(II) chloride pentahydrate; entities sensitive to dissolved CO₂;entities sensitive to fatty acids, such as BODIPY 530-labeledglycerophosphoethanolamine; entities sensitive to proteins such as4-amino-4′-benzamidostilbene-2-2′-disulfonic acid (sensitive to serumalbumin), X-Gal or NBT/BCIP (sensitive to certain enzymes), Tb³⁺ fromTbCl₃ (sensitive to certain calcium-binding proteins), BODIPY FLphallacidin (sensitive to actin), or BOCILLIN FL (sensitive to certainpenicillin-binding proteins); entities sensitive to concentration ofglucose, lactose or other components, or entities sensitive toproteases, lactates or other metabolic byproducts, entities sensitive toproteins, antibodies, or other cellular products.

In some cases, a pooled region of fluid, such as a suction blister, maybe formed in the skin to facilitate delivery and/or withdrawal of fluidfrom the skin. Thus, certain aspects of the present invention aregenerally directed to the creation of suction blisters or other pooledregions of fluid within the skin. In one set of embodiments, a pooledregion of fluid can be created between the dermis and epidermis of theskin. Suction blisters or other pooled regions may form in a manner suchthat the suction blister or other pooled region is not significantlypigmented in some cases, since the basal layer of the epidermis containsmelanocytes, which are responsible for producing pigments. Such regionscan be created by causing the dermis and the epidermis to at leastpartially separate, and as will be discussed below, a number oftechniques can be used to at least partially separate the dermis fromthe epidermis.

In one technique, a pool of interstitial fluid is formed between layersof skin of a subject and, after forming the pool, fluid is drawn fromthe pool by accessing the fluid through a layer of skin, for example,puncturing the outer layer of skin with one or more microneedles.Specifically, for example, a suction blister can be formed and then thesuction blister can be punctured and fluid can be drawn from theblister. In another technique, an interstitial region can be accessedand fluid drawn from that region without first forming a pool of fluidvia a suction blister or the like. For example, a microneedle ormicroneedles can be applied to the interstitial region and fluid can bedrawn therefrom. Where microneedles are used, it can be advantageous toselect needles of length such that interstitial fluid is preferentiallyobtained and, where not desirable, blood is not accessed.

Pooled regions of fluids may be formed on any suitable location withinthe skin of a subject. Factors such as safety or convenience may be usedto select a suitable location, as (in humans) the skin is relativelyuniform through the body, with the exception of the hands and feet. Asnon-limiting examples, the pooled region may be formed on an arm or aleg, on the chest, abdomen, or the back of the subject, or the like. Thesize of the pooled region of fluid that is formed in the skin and/or theduration that the pooled region lasts within the skin depends on avariety of factors, such as the technique of creating the pooled region,the size of the pooled region, the size of the region of skin to whichthe technique is applied, the amount of fluid withdrawn from the pooledregion (if any), any materials that are delivered into the pooledregion, or the like. For example, if vacuum is applied to the skin tocreate a suction blister, the vacuum applied to the skin, the durationof the vacuum, and/or the area of the skin affected may be controlled tocontrol the size and/or duration of the suction blister. In someembodiments, it may be desirable to keep the pooled regions relativelysmall, for instance, to prevent an unsightly visual appearance, to allowfor greater sampling accuracy (due to a smaller volume of material), orto allow for more controlled placement of particles within the skin. Forexample, the volume of the pooled region may be kept to less than about2 ml or less than about 1 ml in certain cases, or the average diameterof the pooled region (i.e., the diameter of a circle having the samearea as the pooled region) may be kept to less than about 5 cm, lessthan about 4 cm, less than about 3 cm, less than about 2 cm, less thanabout 1 cm, less than about 5 mm, less than about 4 mm, less than about3 mm, less than about 2 mm, or less than about 1 mm.

A variety of techniques may be used to cause pooled regions of fluid toform within the skin. In one set of embodiments, vacuum is applied tocreate a suction blister, or otherwise used to collect blood orinterstitial fluid from a subject. In other embodiments, however, othermethods may be used to create as a pooled region of fluid within theskin besides, or in addition to, the use of vacuum. When vacuum (i.e.,the amount of pressure below atmospheric pressure, such that atmosphericpressure has a vacuum of 0 mmHg, i.e., the pressure is gauge pressurerather than absolute pressure) is used to at least partially separatethe dermis from the epidermis to cause the pooled region to form, thepooled region of fluid thus formed can be referred to as a suctionblister. For example, vacuums of at least about 50 mmHg, at least about100 mmHg, at least about 150 mmHg, at least about 200 mmHg, at leastabout 250 mmHg, at least about 300 mmHg, at least about 350 mmHg, atleast about 400 mmHg, at least about 450 mmHg, at least about 500 mmHg,at least about 550 mmHg, at least about 600 mmHg, at least about 650mmHg, at least about 700 mmHg, or at least about 750 mmHg may be appliedto the skin, e.g., to cause a suction blister and/or to collect blood orinterstitial fluid from a subject (as discussed, these measurements arenegative relative to atmospheric pressure. Different amounts of vacuummay be applied to different subjects in some cases, for example, due todifferences in the physical characteristics of the skin of the subjects.

The vacuum may be applied to any suitable region of the skin, and thearea of the skin to which the vacuum may be controlled in some cases.For instance, the average diameter of the region to which vacuum isapplied may be kept to less than about 5 cm, less than about 4 cm, lessthan about 3 cm, less than about 2 cm, less than about 1 cm, less thanabout 5 mm, less than about 4 mm, less than about 3 mm, less than about2 mm, or less than about 1 mm. In addition, such vacuums may be appliedfor any suitable length of time at least sufficient to cause at leastsome separation of the dermis from the epidermis to occur. For instance,vacuum may be applied to the skin for at least about 1 min, at leastabout 3 min, at least about 5 min, at least about 10 min, at least about15 min, at least about 30 min, at least about 1 hour, at least about 2hours, at least about 3 hours, at least about 4 hours, etc. Examples ofdevices suitable for creating such suction blisters are discussed inmore detail below. In other cases, however, bodily fluids such as bloodor interstitial fluid may be withdrawn from the skin and/or beneath theskin using vacuum without the creation of a suction blister. Othernon-limiting examples of fluids include saliva, sweat, tears, mucus,plasma, lymph, or the like.

Other methods besides vacuum may be used to cause such separation tooccur. For example, in another set of embodiments, heat may be used. Forinstance, a portion of the skin may be heated to at least about 40° C.,at least about 50° C., at least about 55° C., or at least about 60° C.,using any suitable technique, to cause such separation to occur. Theskin may be heated, for instance, using an external heat source (e.g.,radiant heat or a heated water bath), a chemical reaction,electromagnetic radiation (e.g., microwave radiation, infraredradiation, etc.), or the like. In some cases, the radiation may befocused on a relatively small region of the skin, e.g., to at leastpartially spatially contain the amount of heating within the skin thatoccurs.

In yet another set of embodiments, a separation chemical may be appliedto the skin to at least partially cause separation of the dermis and theepidermis to occur. Non-limiting examples of such separation chemicalsinclude proteases such as trypsin, purified human skin tryptase, orcompound 48/80. Separation compounds such as these are commerciallyavailable from various sources. The separation chemical may be applieddirectly to the skin, e.g., rubbed into the surface of the skin, or insome cases, the separation chemical can be delivered into the subject,for example, between the epidermis and dermis of the skin. Theseparation chemical can, for example, be injected in between the dermisand the epidermis.

Another example of a separation chemical is a blistering agent, such aspit viper venom or blister beetle venom. Non-limiting examples ofblistering agents include phosgene oxime, Lewisite, sulfur mustards(e.g., mustard gas or 1,5-dichloro-3-thiapentane,1,2-bis(2-chloroethylthio)ethane, 1,3-bis(2-chloroethylthio)-n-propane,1,4-bis(2-chloroethylthio)-n-butane,1,5-bis(2-chloroethylthio)-n-pentane, 2-chloroethylchloromethylsulfide,bis(2-chloroethyl)sulfide, bis(2-chloroethylthio)methane,bis(2-chloroethylthiomethyl)ether, or bis(2-chloroethylthioethyl)ether),or nitrogen mustards (e.g., bis(2-chloroethyl)ethylamine,bis(2-chloroethyl)methylamine, or tris(2-chloroethyl)amine).

In still another set of embodiments, a device may be inserted into theskin and used to mechanically separate the epidermis and the dermis, forexample, a wedge or a spike. Fluids may also be used to separate theepidermis and the dermis, in yet another set of embodiments. Forexample, saline or another relatively inert fluid may be injected intothe skin between the epidermis and the dermis to cause them to at leastpartially separate.

These and/or other techniques may also be combined, in still otherembodiments. For example, in one embodiment, vacuum and heat may beapplied to the skin of a subject, sequentially and/or simultaneously, tocause such separation to occur. As a specific example, in oneembodiment, vacuum is applied while the skin is heated to a temperatureof between about 40° C. and about 50° C.

In another aspect, the present invention is directed to a kit includingone or more of the compositions previously discussed, e.g., a kitincluding a device for the delivery and/or withdrawal of fluid from theskin and/or beneath the skin, a kit including a device able to create apooled region of fluid within the skin of a subject, a kit including adevice able to determine a fluid, a kit including a drug (or othersubstance) and a device able to determine the drug (or other substance)within the skin, or the like. An example of a kit containing more thanone device of the invention is illustrated in FIG. 2D, with kit 150containing devices 152. A “kit,” as used herein, typically defines apackage or an assembly including one or more of the compositions ordevices of the invention, and/or other compositions or devicesassociated with the invention, for example, as previously described. Forexample, in one set of embodiments, the kit may include a device and oneor more compositions for use with the device. Each of the compositionsof the kit, if present, may be provided in liquid form (e.g., insolution), or in solid form (e.g., a dried powder). In certain cases,some of the compositions may be constitutable or otherwise processable(e.g., to an active form), for example, by the addition of a suitablesolvent or other species, which may or may not be provided with the kit.Examples of other compositions or components associated with theinvention include, but are not limited to, solvents, surfactants,diluents, salts, buffers, emulsifiers, chelating agents, fillers,antioxidants, binding agents, bulking agents, preservatives, dryingagents, antimicrobials, needles, syringes, packaging materials, tubes,bottles, flasks, beakers, dishes, frits, filters, rings, clamps, wraps,patches, containers, tapes, adhesives, and the like, for example, forusing, administering, modifying, assembling, storing, packaging,preparing, mixing, diluting, and/or preserving the compositionscomponents for a particular use, for example, to a sample and/or asubject.

A kit of the invention may, in some cases, include instructions in anyform that are provided in connection with the compositions of theinvention in such a manner that one of ordinary skill in the art wouldrecognize that the instructions are to be associated with thecompositions of the invention. For instance, the instructions mayinclude instructions for the use, modification, mixing, diluting,preserving, administering, assembly, storage, packaging, and/orpreparation of the compositions and/or other compositions associatedwith the kit. In some cases, the instructions may also includeinstructions for the delivery and/or administration of the compositions,for example, for a particular use, e.g., to a sample and/or a subject.The instructions may be provided in any form recognizable by one ofordinary skill in the art as a suitable vehicle for containing suchinstructions, for example, written or published, verbal, audible (e.g.,telephonic), digital, optical, visual (e.g., videotape, DVD, etc.) orelectronic communications (including Internet or web-basedcommunications), provided in any manner.

In some embodiments, the present invention is directed to methods ofpromoting one or more embodiments of the invention as discussed herein.As used herein, “promoted” includes all methods of doing businessincluding, but not limited to, methods of selling, advertising,assigning, licensing, contracting, instructing, educating, researching,importing, exporting, negotiating, financing, loaning, trading, vending,reselling, distributing, repairing, replacing, insuring, suing,patenting, or the like that are associated with the systems, devices,apparatuses, articles, methods, compositions, kits, etc. of theinvention as discussed herein. Methods of promotion can be performed byany party including, but not limited to, personal parties, businesses(public or private), partnerships, corporations, trusts, contractual orsub-contractual agencies, educational institutions such as colleges anduniversities, research institutions, hospitals or other clinicalinstitutions, governmental agencies, etc. Promotional activities mayinclude communications of any form (e.g., written, oral, and/orelectronic communications, such as, but not limited to, e-mail,telephonic, Internet, Web-based, etc.) that are clearly associated withthe invention.

In one set of embodiments, the method of promotion may involve one ormore instructions. As used herein, “instructions” can define a componentof instructional utility (e.g., directions, guides, warnings, labels,notes, FAQs or “frequently asked questions,” etc.), and typicallyinvolve written instructions on or associated with the invention and/orwith the packaging of the invention. Instructions can also includeinstructional communications in any form (e.g., oral, electronic,audible, digital, optical, visual, etc.), provided in any manner suchthat a user will clearly recognize that the instructions are to beassociated with the invention, e.g., as discussed herein.

The following documents are incorporated herein by reference: U.S.Provisional Patent Application Ser. No. 61/058,796, filed Jun. 4, 2008,titled “Compositions and Methods for Diagnostics, Therapies, and OtherApplications”; U.S. Provisional Patent Application Ser. No. 61/163,791,filed Mar. 26, 2009, titled “Composition and Methods for Rapid One-StepDiagnosis”; U.S. Provisional Patent Application Ser. No. 61/163,793,filed Mar. 26, 2009, titled “Compositions and Methods for Diagnostics,Therapies, and Other Applications”; U.S. patent application Ser. No.12/478,756, filed Jun. 4, 2009, titled “Compositions and Methods forDiagnostics, Therapies, and Other Applications”; International PatentApplication No. PCT/US09/046333, filed Jun. 4, 2009, titled“Compositions and Methods for Diagnostics, Therapies, and OtherApplications”; U.S. Provisional Patent Application Ser. No. 61/163,710,filed Mar. 26, 2009, titled “Systems and Methods for Creating and UsingSuction Blisters or Other Pooled Regions of Fluid within the Skin”; U.S.Provisional Patent Application Ser. No. 61/163,733, filed Mar. 26, 2009,titled “Determination of Tracers within Subjects”; U.S. ProvisionalPatent Application Ser. No. 61/163,750, filed Mar. 26, 2009, titled“Monitoring of Implants and Other Devices”; U.S. Provisional PatentApplication Ser. No. 61/154,632, filed Mar. 2, 2009, titled “OxygenSensor”; and U.S. Provisional Patent Application Ser. No. 61/269,436,filed Jun. 24, 2009, titled “Devices and Techniques associated withDiagnostics, Therapies, and Other Applications, IncludingSkin-Associated Applications.”

Also incorporated by reference herein are U.S. Provisional PatentApplication Ser. No. 61/263,882, filed Nov. 24, 2009, titled“Patient-Enacted Sampling Technique”; U.S. Provisional PatentApplication Ser. No. 61/294,543, filed Jan. 13, 2010, titled “BloodSampling Device and Method”; U.S. patent application Ser. No.12/716,222, filed Mar. 2, 2010, titled “Oxygen Sensor,” by Levinson, etal.; U.S. patent application Ser. No. 12/716,233, filed Mar. 2, 2010,titled “Systems and Methods for Creating and Using Suction Blisters orOther Pooled Regions of Fluid within the Skin,” by Levinson, et al.;U.S. patent application Ser. No. 12/716,226, filed Mar. 2, 2010, titled“Techniques and Devices Associated with Blood Sampling,” by Levinson, etal.; and U.S. patent application Ser. No. 12/716,229, filed Mar. 2,2010, titled “Devices and Techniques Associated with Diagnostics,Therapies, and Other Applications, Including Skin-AssociatedApplications,” by Bernstein, et al.

Also incorporated herein by reference are the following applications:U.S. Provisional Patent Application Ser. No. 61/256,874, filed Oct. 30,2009, titled “Systems and Methods for Application to Skin and Control ofUse Thereof,” by Bernstein, et al.; U.S. Provisional Patent ApplicationSer. No. 61/256,880, filed Oct. 30, 2009, titled “Systems and Methodsfor Altering or Masking Perception of Treatment of a Subject,” byChickering, et al. and U.S. Provisional Patent Application Ser. No.61/256,871, filed Oct. 30, 2009, titled “Packaging Systems and Methodsfor Devices Applied to the Skin,” By Bernstein, et al. In addition, thefollowing are incorporated by reference herein: U.S. Provisional PatentApplication Ser. No. 61/256,863, filed Oct. 30, 2009, titled “Systemsand Methods for Treating or Shielding Blood on the Surface of the Skin,”by Bernstein, et al.; U.S. Provisional Patent Application Ser. No.61/256,910, filed Oct. 30, 2009, titled “Systems and Methods forSanitizing or Treating the Skin or Devices Applied to the Skin,” byBernstein, et al.; U.S. Provisional Patent Application Ser. No.61/256,931, filed Oct. 30, 2009, titled “Modular Systems for Applicationto the Skin,” by Bernstein, et al.; U.S. Provisional Patent ApplicationSer. No. 61/256,933, filed Oct. 30, 2009, titled “Relatively SmallDevices Applied to the Skin and Methods of Use Thereof,” by Chickering,et al.; U.S. Provisional Patent Application Ser. No. 61/294,543, filedJan. 13, 2010, titled “Blood Sampling Device and Method,” by Chickering,et al.; U.S. Provisional Patent Application Ser. No. 61/334,533, filedMay 13, 2010, titled “Rapid Delivery and/or Withdrawal of Fluids,” byChickering, et al.; U.S. Provisional Patent Application Ser. No.61/334,529, filed May 13, 2010, titled “Sampling Device Interfaces,” byChickering, et al.; U.S. Provisional Patent Application Ser. No.61/357,582, filed Jun. 23, 2010, titled “Sampling Devices and MethodsInvolving Relatively Little Pain,” by Chickering, et al.; U.S.Provisional Patent Application Ser. No. 61/367,607, filed Jul. 26, 2010,titled “Rapid Delivery and/or Withdrawal of Fluids,” by Davis, et al.;and U.S. Provisional Patent Application Ser. No. 61/373,764, filed Aug.13, 2010, titled “Clinical and/or Consumer Techniques and Devices,” byChickering, et al.

It should be understood that as used herein, references to “another”embodiment or set of embodiments does not imply that any particularembodiments are incompatible or mutually exclusive with any otherembodiment; instead, it is contemplated that one embodiment and“another” embodiment may be combined in any instance unless they areclearly physically incompatible with each other.

While several embodiments of the present invention have been describedand illustrated herein, those of ordinary skill in the art will readilyenvision a variety of other means and/or structures for performing thefunctions and/or obtaining the results and/or one or more of theadvantages described herein, and each of such variations and/ormodifications is deemed to be within the scope of the present invention.More generally, those skilled in the art will readily appreciate thatall parameters, dimensions, materials, and configurations describedherein are meant to be exemplary and that the actual parameters,dimensions, materials, and/or configurations will depend upon thespecific application or applications for which the teachings of thepresent invention is/are used. Those skilled in the art will recognize,or be able to ascertain using no more than routine experimentation, manyequivalents to the specific embodiments of the invention describedherein. It is, therefore, to be understood that the foregoingembodiments are presented by way of example only and that, within thescope of the appended claims and equivalents thereto, the invention maybe practiced otherwise than as specifically described and claimed. Thepresent invention is directed to each individual feature, system,article, material, kit, and/or method described herein. In addition, anycombination of two or more such features, systems, articles, materials,kits, and/or methods, if such features, systems, articles, materials,kits, and/or methods are not mutually inconsistent, is included withinthe scope of the present invention.

All definitions, as defined and used herein, should be understood tocontrol over dictionary definitions, definitions in documentsincorporated by reference, and/or ordinary meanings of the definedterms.

The indefinite articles “a” and “an,” as used herein in thespecification and in the claims, unless clearly indicated to thecontrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in theclaims, should be understood to mean “either or both” of the elements soconjoined, i.e., elements that are conjunctively present in some casesand disjunctively present in other cases. Multiple elements listed with“and/or” should be construed in the same fashion, i.e., “one or more” ofthe elements so conjoined. Other elements may optionally be presentother than the elements specifically identified by the “and/or” clause,whether related or unrelated to those elements specifically identified.Thus, as a non-limiting example, a reference to “A and/or B”, when usedin conjunction with open-ended language such as “comprising” can refer,in one embodiment, to A only (optionally including elements other thanB); in another embodiment, to B only (optionally including elementsother than A); in yet another embodiment, to both A and B (optionallyincluding other elements); etc.

As used herein in the specification and in the claims, “or” should beunderstood to have the same meaning as “and/or” as defined above. Forexample, when separating items in a list, “or” or “and/or” shall beinterpreted as being inclusive, i.e., the inclusion of at least one, butalso including more than one, of a number or list of elements, and,optionally, additional unlisted items. Only terms clearly indicated tothe contrary, such as “only one of” or “exactly one of,” or, when usedin the claims, “consisting of,” will refer to the inclusion of exactlyone element of a number or list of elements. In general, the term “or”as used herein shall only be interpreted as indicating exclusivealternatives (i.e. “one or the other but not both”) when preceded byterms of exclusivity, such as “either,” “one of,” “only one of,” or“exactly one of.” “Consisting essentially of,” when used in the claims,shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “atleast one,” in reference to a list of one or more elements, should beunderstood to mean at least one element selected from any one or more ofthe elements in the list of elements, but not necessarily including atleast one of each and every element specifically listed within the listof elements and not excluding any combinations of elements in the listof elements. This definition also allows that elements may optionally bepresent other than the elements specifically identified within the listof elements to which the phrase “at least one” refers, whether relatedor unrelated to those elements specifically identified. Thus, as anon-limiting example, “at least one of A and B” (or, equivalently, “atleast one of A or B,” or, equivalently “at least one of A and/or B”) canrefer, in one embodiment, to at least one, optionally including morethan one, A, with no B present (and optionally including elements otherthan B); in another embodiment, to at least one, optionally includingmore than one, B, with no A present (and optionally including elementsother than A); in yet another embodiment, to at least one, optionallyincluding more than one, A, and at least one, optionally including morethan one, B (and optionally including other elements); etc.

It should also be understood that, unless clearly indicated to thecontrary, in any methods claimed herein that include more than one stepor act, the order of the steps or acts of the method is not necessarilylimited to the order in which the steps or acts of the method arerecited.

In the claims, as well as in the specification above, all transitionalphrases such as “comprising,” “including,” “carrying,” “having,”“containing,” “involving,” “holding,” “composed of,” and the like are tobe understood to be open-ended, i.e., to mean including but not limitedto. Only the transitional phrases “consisting of” and “consistingessentially of” shall be closed or semi-closed transitional phrases,respectively, as set forth in the United States Patent and TrademarkOffice Manual of Patent Examining Procedures, Section 2111.03.

What is claimed is:
 1. (canceled)
 2. The method of claim 36, whereinpresenting the indication comprises presenting the indication on adisplay screen.
 3. The method of claim 2, wherein the display screenindicates access to a web site.
 4. (canceled)
 5. The method of claim 36,wherein presenting the indication comprises presenting the indicationusing a light.
 6. The method of claim 36, wherein the external responsecomprises a coupon.
 7. The method of claim 36, wherein the externalresponse comprises a monetary response.
 8. The method of claim 36,wherein the external response comprises a visual display.
 9. The methodof claim 36, wherein the external response comprises music.
 10. Themethod of claim 36, wherein the external response comprises a movie. 11.The method of claim 36, wherein the external response comprises anadvertisement. 12-35. (canceled)
 36. A method, comprising: receivinginformation in a device, the information obtained from a subjectrepresenting a property of a species withdrawn from the subject; andpresenting an indication within the device of an external response to auser based on the received information.
 37. The method of claim 36,wherein the user that the external response is presented to is thesubject.
 38. The method of claim 36, wherein the user that the externalresponse is presented to is a caregiver for the subject.
 39. The methodof claim 36, wherein the information represents an amount and/orconcentration of the species.
 40. The method of claim 36, wherein thereceived information is determined using a device fastened to the skinof the subject.
 41. The method of claim 36, wherein the information isreceived wirelessly.
 42. The method of claim 36, wherein the externalresponse is presented using a web page. 43-65. (canceled)
 66. A device,comprising: means for withdrawing a species from a subject using adevice fastened to the subject; means for determining informationcomprising an amount and/or a concentration of the species using atleast the device; and means for transmitting the information to acomputing device, wherein the computing device is configured to provide,via an output device, non-number feedback to the subject based on thetransmitted information.
 67. (canceled)
 68. The device of claim 66,wherein the output device provides visual feedback.
 69. The device ofclaim 66, wherein the output device provides auditory feedback.
 70. Thedevice of claim 66, wherein the output device provides music.
 71. Thedevice of claim 66, wherein the species is contained in blood withdrawnfrom the subject.
 72. The device of claim 66, wherein the means forwithdrawing the species comprises a needle.
 73. The device of claim 66,wherein the means for withdrawing the species comprises a microneedle.74. The device of claim 66, wherein the means for withdrawing thespecies comprises a self-contained vacuum chamber.
 75. The device ofclaim 66, wherein the means for transmitting comprises means fortransmitting the information wirelessly.